How to Query DTCs for your vehicle and generate in Home Assistant the Code and text strings

[wambs]

Below are the instructions to Query DTCs for your vehicle and generate in Home Assistant the Code and text strings. This is very involved but for me very worth it!!

Note ***, This requires the Beta 9 SW from https://github.com/wambs/wican-fw/releases

To get you DTCs code to String, will require you to search for your car manufacture.

Phase 1: Creating the DTC Query in the WiCAN Web UI
We will configure the WiCAN to broadcast a Mode 03 command, process the hex data through your custom C-firmware, and publish it directly to a dedicated MQTT topic.

1. Open your WiCAN Pro Web UI in your browser.

2. Navigate to the Custom PIDs (or Vehicle) section.

3. Click Add New PID and configure the fields exactly like this:

   • Create a new Group with init: ATTP6;ATSH7DF;ATCRA;
   • Add a new PID to the group
   • Name: Active DTCs (This dictates your JSON key in the payload, e.g., dtcs_raw)
   • MQTT_Topic: homeassistant/wican/your_car/dtcs (This explicitly routes this specific PID's data to its own topic)
   • PID (Command): 03 (The OBD2 standard for Requesting DTCs)
   • Expression (Expr): RAW (Triggers our custom C loop to merge the multi-frame ISO-TP data)
   • Polling Interval: 60000 (60 seconds prevents choking the CAN bus)

Once saved, your WiCAN will begin broadcasting to your new dedicated topic. The payload arriving at homeassistant/wican/your_car/dtcs will look like this: {"dtc_raw": "4303C60FC68B2104"}. If you have no active DTCs will look like this: {"dtc_raw": "4300"}.

Phase 2: The Home Assistant Sensor (configuration.yaml)

1. Now we ingest that optimized hex string from your new dedicated topic.
2. Open your Home Assistant configuration.yaml file.

Add the following under your mqtt: -> sensor: block. Notice that both topics now point strictly to the dtcs path.

      - name: "F-350 Active DTCs"
        default_entity_id: "sensor.f350_dtcs"
        unique_id: "f350_dtcs"
        device: *f350_device
        state_topic: "homeassistant/wican/f350/dtcs"
        icon: mdi:engine-outline
        # 1. Keep the main state under 255 characters
        value_template: >-
          {%- set ns = namespace(payload='') -%}

          {# Safety check: Only loop items if it's actually a JSON dictionary #}
          {%- if value_json is defined and value_json is mapping -%}
            {%- for key, val in value_json.items() -%}
              {%- set clean_val = val | string | replace(' ', '') | upper -%}
              {%- set idx = clean_val.find('43') -%}
              {%- if idx != -1 -%}
                {%- set ns.payload = clean_val[idx:] -%}
              {%- endif -%}
            {%- endfor -%}
          {%- else -%}
            {# If it's a raw string, bypass JSON parsing entirely #}
            {%- set clean_val = value | string | replace(' ', '') | upper -%}
            {%- set idx = clean_val.find('43') -%}
            {%- if idx != -1 -%}
              {%- set ns.payload = clean_val[idx:] -%}
            {%- endif -%}
          {%- endif -%}

          {%- if ns.payload.startswith('43') and ns.payload | length >= 4 -%}
            {%- set count = ns.payload[2:4] | int(base=16, default=0) -%}
            {{- 'System Clear' if count == 0 else count ~ ' Active Codes' -}}
          {# THE MEMORY FIX: If the payload is bad/missing, echo our own last known state! #}
          {%- elif states('sensor.f350_dtcs') not in ['unknown', 'unavailable'] -%}
            {{- states('sensor.f350_dtcs') -}}
            
          {# If Home Assistant freshly rebooted and has no history, default to quiet. #}
          {%- else -%}
            System Clear
          {%- endif -%}

        json_attributes_topic: "homeassistant/wican/f350/dtcs"
        json_attributes_template: >-
          {%- from 'ford_dtc.jinja' import get_meaning -%}
          {%- set ns = namespace(payload='', codes=[], details=[]) -%}

          {%- if value_json is defined and value_json is mapping -%}
            {%- for key, val in value_json.items() -%}
              {%- set clean_val = val | string | replace(' ', '') | upper -%}
              {%- set idx = clean_val.find('43') -%}
              {%- if idx != -1 -%}
                {%- set ns.payload = clean_val[idx:] -%}
              {%- endif -%}
            {%- endfor -%}
          {%- else -%}
            {%- set clean_val = value | string | replace(' ', '') | upper -%}
            {%- set idx = clean_val.find('43') -%}
            {%- if idx != -1 -%}
              {%- set ns.payload = clean_val[idx:] -%}
            {%- endif -%}
          {%- endif -%}

          {%- set count = 0 -%}
          {# CHANGED TO [:2] SLICING TO PREVENT SAFESTRING CRASH #}
          {%- if ns.payload[:2] == '43' and ns.payload | length >= 4 -%}
            {%- set count = ns.payload[2:4] | int(0, 16) -%}
            {%- if count > 0 -%}
              {%- set prefix_map = {
                '0':'P0', '1':'P1', '2':'P2', '3':'P3',
                '4':'C0', '5':'C1', '6':'C2', '7':'C3',
                '8':'B0', '9':'B1', 'A':'B2', 'B':'B3',
                'C':'U0', 'D':'U1', 'E':'U2', 'F':'U3'
              } -%}
              {%- set codes_string = ns.payload[4:] -%}
              {%- for i in range(0, count * 4, 4) -%}
                {%- set hex_code = codes_string[i:i+4] -%}
                {%- if hex_code | length == 4 -%}
                  {%- set first_char = hex_code[0] -%}
                  {%- if first_char in prefix_map -%}
                    {%- set dtc = prefix_map[first_char] ~ hex_code[1:4] -%}
                    {%- set meaning = get_meaning(dtc) | trim -%}
                    {%- set ns.codes = ns.codes + [dtc] -%}
                    {%- set ns.details = ns.details + [dtc ~ ': ' ~ meaning] -%}
                  {%- endif -%}
                {%- endif -%}
              {%- endfor -%}
            {%- endif -%}
          {%- endif -%}

          {# DIAGNOSTIC X-RAY ADDED TO JSON OUTPUT #}
          {{- {"active_codes": ns.codes, "descriptions": ns.details, "debug_payload": ns.payload, "debug_count": count} | tojson -}}

Phase 3: The Dictionary Macro
For the above YAML to work, Home Assistant needs the dictionary file to look up the English definitions.

1. In your Home Assistant config directory (where configuration.yaml lives), create a folder named exactly custom_templates.
2. Inside that folder, create a file named ford_dtc.jinja.
3. Paste your mapping macro inside it

{% macro get_meaning(dtc) %}
{% set dtc_map = {
  'U060F': 'Lost Communication with Mass or Volumn Air Flow Sensor A',
  'U068B': 'Lost Communication with Turbocharger/Supercharger Inlet Pressure Sensor A',
  'P2104': 'Electronic Throttle Control System - Forced Idle'
  /* ... paste your entire factory list here ... */
} %}
{{ dtc_map.get(dtc, 'Unknown Code - Refer to Factory Service Manual') }}
{% endmacro %}

Crucial Step: Restart Home Assistant completely so it registers the new .jinja file and applies the configuration.yaml changes.

Phase 4: The Dashboard UI
Finally, we build the interactive dashboard element. This uses a custom button that blinks amber when codes exist, clears the codes on a long press, and drops down a formatted text box of your faults on a single tap.

1. Go to Settings > Devices & Services > Helpers and create a Toggle helper named Show F350 Codes (this creates input_boolean.show_f350_codes).
2. Add this YAML to your Lovelace dashboard:

type: vertical-stack
cards:
  # 1. THE INTERACTIVE CHECK ENGINE BUTTON
  - type: custom:button-card
    entity: sensor.f350_active_dtcs
    name: CHECK ENGINE
    icon: mdi:engine
    show_name: true
    show_icon: true
    
    tap_action:
      # Tapping toggles the dropdown list
      action: call-service
      service: input_boolean.toggle
      service_data:
        entity_id: input_boolean.show_f350_codes
        
    hold_action:
      # Long press sends Mode 04 to wipe the codes and turn off the CEL
      action: call-service
      service: mqtt.publish
      service_data:
        # ---> BASE TX TOPIC TO CLEAR CODES <---
        topic: "homeassistant/wican/your_car/tx" 
        payload: "04\r"
        
    styles:
      card:
        - width: 110px
        - height: 110px
        - background-color: '#1a1a1a'
      icon:
        - width: 50px
      name:
        - font-size: 10px
        - font-weight: bold
        
    state:
      - value: System Clear
        color: '#333333'
        styles:
          card:
            - border: none
          icon:
            - color: '#444'
            - animation: none
          name:
            - color: '#444'
            
      - operator: default
        color: '#FF9800'
        styles:
          card:
            - border: 2px solid #FF9800
          icon:
            - color: '#FF9800'
            - animation: blink 1.2s ease infinite
          name:
            - color: '#FF9800'
            
    extra_styles: |
      @keyframes blink {
        0% { opacity: 1; }
        50% { opacity: 0.2; }
        100% { opacity: 1; }
      }

  # 2. THE DROPDOWN CODE LIST
  - type: conditional
    conditions:
      - entity: input_boolean.show_f350_codes
        state: 'on'
    card:
      type: markdown
      title: "⚠️ Active Diagnostic Codes"
      content: >
        {% set codes = state_attr('sensor.f350_active_dtcs', 'descriptions') %}
        
        {% if codes %}
          {% for code in codes %}
            * **{{ code.split(':')[0] }}**: {{ code.split(':')[1] }}
          {% endfor %}
        {% else %}
          ✅ System Clear. No active codes detected.
        {% endif %}

[jaymik]

Finally getting around to setting this up! I have a couple question:

1. On the WiCAN configuration page, does MQTT need to be enabled under the WiCAN Pro Settings?
2. On the WiCAN configuration page, does the Home Assistant section under Automate need to be filled out in any specific way?
   • Right now all I have under this section is:
     • WebHook: enable
     • WebHook Data Mode: Changed Values Only
3. The setup fields for the vehicle group didn't quite match what I see in my Automate Parameters section. Can you confrim if this is correct?

[wambs]

Yes, if want to MQTT, you must enable it under the WiCAN Pro Settings. If you plan on only using MQTT, you don't need to enable webhooks. Make sure you fill in the "filed name" and "Description". "field name is used by the MQTT in HA to decode the MQTT json for the entity. Make sure expression is DTC_RAW, previous examples are no longer correct. Also, make sure your using Beta 14, whcih has some importtant updates for trouble codes. https://github.com/wambs/wican-fw/releases/

My Req trouble codes PID example below:

[jaymik]

Making progress now that WiCAN messages show up in MQTT Explorer!

However, I'm still not getting DTC codes. I ran the query on the WiCAN directly and got a "no data" message, making me think I still don't have WiCAN configured correctly.

Additionally, I know for sure I loaded the .bin for v14, but the status page still shows v12. Is that a clue or a red herring?

[jaymik]

I seem to have an MQTT setting still not set correctly since the MQTT explorer running on Home Assistant is not showing the dtcs key:

My MQTT settings on the WiCAN are as follows:

I've tried all the combinations I can think of, but still no luck.

[jaymik]

Hey @wambs , just wondering if you saw my post here? I'm combing through the source code to figure out what's missing. I was able to find the raw data show up briefly under homeassistant/wican/you_car/rx, but it seems like that key is simply getting all receipts and doesn't explain why there isn't a key showing up under homeassistant/wican/you_car/dtcs.

[wambs]

Sorry, didn't get post. The DTCs processing was broken, Released GUI Beta 16.

https://github.com/wambs/wican-fw/releases/tag/WiCAN-Pro-Beta-16

[wambs]

The version is OK, thats the internal version Git creates when I build the firmware. Make sure the car is running when requesting the trouble code.

…

On Thu, Apr 30, 2026 at 9:40 PM jaymik ***@***.***> wrote: Making progress now that WiCAN messages show up in MQTT Explorer! However, I'm still not getting DTC codes. I ran the query on the WiCAN directly and got a "no response" message, making me think I still don't have WiCAN configured correctly. 7F1C7D61-594D-4472-AD09-97D3FC00B7EB.jpeg (view on web) <https://github.com/user-attachments/assets/98db08b8-7c93-4269-9dd3-fef7a64e13f8> 67628360-E756-4359-B886-9E3FAB0C3C9B.jpeg (view on web) <https://github.com/user-attachments/assets/318ae804-6a3c-4ca6-b41a-0c0ea9152097> Additionally, I know for sure I loaded the .bin for v14, but the status page still shows v12. Is that a clue or a red herring? 81F75E8B-B768-4E43-ACF3-E12D5177E051.jpeg (view on web) <https://github.com/user-attachments/assets/aa7fa065-8774-445e-b208-bc3286c1b0c9> — Reply to this email directly, view it on GitHub <#10 (reply in thread)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ADH3ULGWNBQ6A6BDYZIKK5L4YQFABAVCNFSM6AAAAACWVTF43KVHI2DSMVQWIX3LMV43URDJONRXK43TNFXW4Q3PNVWWK3TUHMYTMNZXGYYTKMY> . Triage notifications on the go with GitHub Mobile for iOS <https://apps.apple.com/app/apple-store/id1477376905?ct=notification-email&mt=8&pt=524675> or Android <https://play.google.com/store/apps/details?id=com.github.android&referrer=utm_campaign%3Dnotification-email%26utm_medium%3Demail%26utm_source%3Dgithub>. You are receiving this because you authored the thread.Message ID: ***@***.***>

[jaymik]

I can confirm my car was running when using that test button, snd that codes are available since the check engine light is on, and the WiCAN can pull codes when set up to use CarScanner.

[wambs]

In the settings page, under CAN tab, make sure Protocol: is set to AutoPID.
CAN Bitrate: should probably be 500K, this can dependent on car

My Settings:

[jaymik]

Still not working

I confirmed my settings match yours, and I know 500000 baud is correct since standard PIDs work (currently disabled for this troubleshooting.

Any other ideas I can try?

[jaymik]

Also, here's my settings JSON

{
    "config":{
        "wifi_mode":"Station",
        "ap_ch":"6",
        "ap_ssid_en":"disable",
        "ap_ssid":"",
        "webhook_en":"disable",
        "sta_ssid":"removed",
        "sta_pass":"removed",
        "sta_security":"wpa3",
        "home_ssid":"",
        "home_password":"removed",
        "home_security":"removed",
        "drive_ssid":"",
        "drive_password":"",
        "drive_security":"removed",
        "home_protocol":"elm327",
        "drive_protocol":"elm327",
        "drive_connection_type":"wifi",
        "drive_mode_timeout":"60",
        "can_datarate":"500K",
        "can_mode":"normal",
        "port_type":"tcp",
        "port":"35000",
        "ap_pass":"removed",
        "protocol":"auto_pid",
        "ble_pass":"removed",
        "ble_status":"disable",
        "ble_power":"9",
        "sleep_status":"disable",
        "sleep_disable_agree":"yes",
        "periodic_wakeup":"disable",
        "sleep_volt":"12",
        "sleep_time":"16",
        "wakeup_interval":"5",
        "batt_alert":"disable",
        "batt_alert_ssid":"MeatPi",
        "batt_alert_pass":"removed",
        "batt_alert_volt":"11.0",
        "batt_alert_protocol":"mqtt",
        "batt_alert_url":"mqtt://mqtt.eclipseprojects.io",
        "batt_alert_port":"1883",
        "batt_alert_topic":"CAR1/voltage",
        "batt_alert_time":"1",
        "batt_mqtt_user":"removed",
        "batt_mqtt_pass":"removed",
        "mqtt_en":"enable",
        "mqtt_url":"mqtt://192.168.1.141",
        "mqtt_port":"1883",
        "mqtt_user":"removed",
        "mqtt_pass":"removed",
        "mqtt_security":"none",
        "mqtt_cert_set":"default",
        "mqtt_skip_cn":"disable",
        "mqtt_tx_topic":"wican/94a9901b1951/can/tx",
        "ap_auto_disable":"disable",
        "mqtt_tx_en":"enable",
        "mqtt_rx_topic":"wican/94a9901b1951/can/rx",
        "mqtt_rx_en":"enable",
        "mqtt_status_topic":"wican/94a9901b1951/can/status",
        "mqtt_elm327_log":"disable",
        "logger_status":"enable",
        "log_filesystem":"fatfs",
        "log_storage":"sdcard",
        "log_period":"60",
        "imu_threshold":"8",
        "elm327_udp_log":"disable",
        "sta_ip_type":"dhcp",
        "sta_static_ip":"",
        "sta_netmask":"",
        "sta_gateway":"",
        "sta_dns":"",
        "sta_fallbacks":[],
        "sta_home_priority":"disabled"
    },
    "auto_pid_car_data":{
        "cars":[
            {
                "car_model":"Not Selected",
                "init":"",
                "pids":[],
                "can_filters":[],
                "pid_groups":[
                    {
                        "group_name":"Req Trouble Codes",
                        "enabled":true,
                        "condition":"engine_running",
                        "period":60000,
                        "pids":[
                            {
                                "pid":"03",
                                "pid_description":"Trouble Codes",
                                "enabled":true,
                                "_collapsed":false,
                                "parameters":[
                                    {
                                        "name":"dtc_raw",
                                        "expression":"DTC_RAW",
                                        "unit":"",
                                        "enabled":true,
                                        "onchange":false,
                                        "destination_type":"MQTT_Topic",
                                        "send_to":"homeassistant/wican/your_car/dtcs"
                                    }
                                ]
                            }
                        ],
                        "init":"ATTP6;ATSH7DF;ATCRA;",
                        "_collapsed":false
                    }
                ]
            }
        ]
    },
    "auto_pid":{
        "grouping":"disable",
        "disable_on_sleep_voltage":"disable",
        "pid_polling_min_voltage":13.1,
        "webhook_data_mode":"changed",
        "car_specific":"disable",
        "custom_pids":"disable",
        "ha_discovery":"disable",
        "car_model":"Not Selected",
        "pids":[],
        "std_pids":[
            {
                "Name":"2F-FuelTankLevel",
                "ReceiveHeader":"",
                "Period":"1000",
                "Type":"Default",
                "Send_to":"",
                "enabled":true
            },
            {
                "Name":"01-MonitorStatus",
                "ReceiveHeader":"",
                "Period":"1000",
                "Type":"Default",
                "Send_to":"",
                "enabled":true
            },
            {
                "Name":"1C-OBDStandard",
                "ReceiveHeader":"",
                "Period":"1000",
                "Type":"Default",
                "Send_to":"",
                "enabled":true
            },
            {
                "Name":"03-FuelSystemStatus",
                "ReceiveHeader":"",
                "Period":"1000",
                "Type":"Default",
                "Send_to":"",
                "enabled":true
            },
            {
                "Name":"07-LongFuelTrimBank1",
                "ReceiveHeader":"",
                "Period":"1000",
                "Type":"Default",
                "Send_to":"",
                "enabled":true
            }
        ],
        "can_filters":[],
        "standard_pids":"disable",
        "ecu_protocol":"7",
        "group_api_token":"",
        "destinations":[
            {
                "type":"Default",
                "destination":"",
                "cycle":5000,
                "api_token":"",
                "cert_set":"default",
                "enabled":true,
                "auth":{
                    "type":"none"
                },
                "query_params":[],
                "success_count":252,
                "fail_count":0,
                "collapsed":true
            }
        ],
        "cars":[
            {
                "car_model":"Not Selected",
                "init":"",
                "pids":[],
                "can_filters":[],
                "pid_groups":[
                    {
                        "group_name":"Req Trouble Codes",
                        "enabled":true,
                        "condition":"engine_running",
                        "period":60000,
                        "pids":[
                            {
                                "pid":"03",
                                "pid_description":"Trouble Codes",
                                "enabled":true,
                                "_collapsed":false,
                                "parameters":[
                                    {
                                        "name":"dtc_raw",
                                        "expression":"DTC_RAW",
                                        "unit":"",
                                        "enabled":true,
                                        "onchange":false,
                                        "destination_type":"MQTT_Topic",
                                        "send_to":"homeassistant/wican/your_car/dtcs"
                                    }
                                ]
                            }
                        ],
                        "init":"ATTP6;ATSH7DF;ATCRA;",
                        "_collapsed":false
                    }
                ]
            }
        ]
    }
}

[wambs]

Your Json settings look OK to me. So, I think the init settings must be different for your vehicle. Using car scanner, capture the the logs and use the same init settings. Below is my current working DTC request.

[jaymik]

That was a good idea! But unfortunately, I still got "No Data".

Looking through the log: I found this:

CustomInitString=ATZ
ATE0
ATH1
ATSP0
ATS0
ATM0
ATAT1

So I updated my init settings to ATZ;ATE0;ATH1;ATSP0;ATS0;ATM0;ATAT1; but it still didn't work. Perhaps I'm looking at the wrong part of the log? I've attached my log in case you can help me make sure the init is correct.
log 3.txt

[wambs]

The vehicle is a Honda using Protocol 7 (ISO 15765-4 CAN, 29-bit ID, 500 kbaud).

Reading DTCs on a 29-bit CAN bus usually requires establishing explicit Flow Control and setting precise Physical Headers for multi-frame responses. Car Scanner does this automatically in the background, but the WiCAN Pro needs these parameters manually defined via AT commands to handle the long diagnostic responses.

Here are the exact AT command sequences extracted from the log to configure the WiCAN Pro for DTCs.

The Base Initialization Sequence
Before querying any modules, the ELM/STN chip on the WiCAN must be initialized to the correct protocol and formatting:

ATE0         // Echo Off (cleaner output)
ATH1         // Headers On (shows module IDs in responses)
ATAL         // Allow Long Messages (required for DTCs)
ATSP7        // Set Protocol to 7 (ISO 15765-4 CAN 29-bit, 500kbps)

Routine 1: Generic OBD2 Emissions DTCs (Service $03)
This queries the entire bus for standard Check Engine Light codes using a functional broadcast.

Send these commands:

ATSH DB33F1  // Set functional broadcast header (18DB33F1)
03           // Request Service 03 (Current DTCs)

Note: If the vehicle has standard emissions codes, they will return here starting with 18DAF... followed by 43 and the hex codes. If clear, you will just get 43 00.

[jaymik]

Nice! I changed the init to ATE0;ATH1;ATAL;ATSP7; and got:

Not sure how to add ATSH DB33F1 as a first command. Here's what I tried:

1. changed the init string ATE0;ATH1;ATAL;ATSP7;ATSH DB33F1; but got the same response as above.
2. added PID ATSH DB33F1 before 03 to the sequence. Got NO DATA on the first PID, and the same response on the 03 PID
3. changed PID 03 to ATSH DB33F1;03 and got NO DATA

Overall, it seems that ATSH DB33F1 didn't make a difference. Am I using that initial command correctly?

[wambs]

So, The WiCAN sent 03, and four different computers inside the Honda replied. that's why you got multiple responses.
ATSH DB33F1 is suppose to tell the CAN Bus you only want one to respond.

Here's a brake down of the info:

1. The Initialization

You used ATE0;ATH1;ATAL;ATSP7;.
This is the perfect baseline. It turns off the echo, turns on the headers so we can see which module is talking, allows long messages, and sets the CAN protocol. Because there are no manual headers, the WiCAN is dynamically routing the 03 broadcast to the entire car.

2. Dissecting the Raw Hex

The WiCAN sent 03, and four different computers inside the Honda replied. Let's translate them:

• 18 DA F1 1D 02 43 00

  • 1D: Transmission Control Module (TCM)
  • 43 00: Positive response (43), but it has 0 codes (00).

• 18 DA F1 03 02 43 00 & 18 DA F1 04 02 43 00

  • These are usually Brake/ABS or Steering controllers.
  • Both responded with 43 00 (0 codes).

• 18 DA F1 11 04 43 01 04 20

  • 11: Powertrain Control Module (The main Engine ECU).
  • 04: Payload length is 4 bytes.
  • 43: Positive response to Service 03.
  • 01: There is exactly 1 code stored.
  • 04 20: This is the raw hex for the trouble code!

3. Translating the Code

In standard OBD2 protocol, the hex 0420 translates directly to the alphanumeric code.

• The first 0 maps to P0 (Powertrain, Generic code).
• The remaining 420 stays the same.

The Honda is currently throwing a P0420 code (Catalyst System Efficiency Below Threshold - Bank 1). This is an incredibly common code for older Hondas, usually pointing to a tired catalytic converter or a lazy downstream O2 sensor.

4. The WiCAN Output

Look at the green parsed text at the bottom: - dtc_raw: 43010420
Because the WiCAN is a smart parser, it saw the four responses, ignored the ones with zero codes, grabbed the payload from the Engine ECU, and grouped it together.

• 43 (Mode 3 Response)
• 01 (Quantity of Codes)
• 0420 (The Code)

[jaymik]

This makes sense. Thank you for the breakdown! If you have resources or reading material I can educate myself with, please forward!

On another note, I left a message on an above thread on mqtt settings that I could use some help on. #10 (reply in thread)

Thanks!

[wambs]

Submitted a fix for the DTCs not sending out via MQTT. Beta 16
https://github.com/wambs/wican-fw/releases/tag/WiCAN-Pro-Beta-16

[jaymik]

I wanted to note for posterity some changes I had to make to get my setup to work:

Phase 2: The Home Assistant Sensor (configuration.yaml)

- active_dtcs_raw
+ dtc_raw

Phase 3: The Dictionary Macro

- /* ... paste your entire factory list here ... */

[wambs]

Glad you got it working. Any cool thing you can do is announcements / cell text msgs when a DTC code is detected.
The script announce_msg_to_all, does my announcements. If I'm not at home, I get a cell text msgs, If I'm at home, I get an voice announcements on my Voice PE devices.

alias: "F-350: New DTC Detected"
description: Alerts Kevin when the truck throws a new diagnostic trouble code.
triggers:

• entity_id: sensor.f350_dtcs
  trigger: state
  conditions:
• condition: template
  value_template: "{{ 'Active Codes' in trigger.to_state.state }}"
• condition: template
  value_template: "{{ trigger.from_state.state == 'System Clear' }}"
  actions:
• action: script.announce_msg_to_all
  data:
  my_message: Attention. The F 350 is reporting {{ trigger.to_state.state }}.
  for_persons: kevin
  mode: single