What does it mean?
B1694 is a Body (airbags, seat belts, body electronics) fault code. It indicates: Accessory Dimming Control Circuit High .
Symptoms
- Panel and switch illumination stays completely off with the lights switched on
- Some illuminated areas work while others stay dark, depending on how the circuit is branched
- Dimmer wheel has no effect at all
- Illumination returns for a while after a connector behind the dash is reseated
- The fault appeared after an audio, cluster or trim installation
Likely causes
- Open circuit in the illumination wiring behind the dashboard
- Instrument cluster, switch pack or heater control panel connector unplugged or a terminal pushed out after previous work
- Illumination bulbs burned out in the switch panels that share this circuit
- LED conversion of the panel lighting drawing too little current for the module to detect a valid load
- Short to battery on the dimming wire, for example from an accessory connected to a permanent live
- Corroded terminals in a connector behind the dash that have lost contact
- Open output driver inside the body control module
How to fix it
- Switch the lights on and note exactly which illuminated components are dead, which narrows down the branch
- Check the illumination fuse and look at the commanded dimming value on live data
- Verify that the connectors at the cluster, the switch packs and the heater controls are fully seated and locked
- Measure the voltage on the dimming wire at a switch pack with the lights on and the dimmer at full brightness
- With the circuit switched off, check continuity of the dimming wire back to the module to locate an open
- Refit original type illumination bulbs if the panel lighting has been converted to LED
- Repair the broken wire or terminal, then test the full dimming range and clear the code