What does it mean?
B1696 is a Body (airbags, seat belts, body electronics) fault code. It indicates: Autolamp On Circuit Short To Ground .
Symptoms
- Headlamps switch on by themselves and stay on regardless of the switch position
- Headlamps cannot be switched off, so the battery goes flat when the vehicle is parked
- Automatic headlamp function does not respond to daylight or darkness
- Headlamps remain on after the ignition is switched off and the delay function never times out
- The switch position and the actual lighting state clearly do not match
Likely causes
- Multifunction or headlamp switch shorted internally, often after liquid has entered the switch
- Chafed wire behind the dashboard or in the steering column loom touching a bracket or the column itself
- Water reaching the switch or the ambient light sensor connector, for example from a leaking windscreen seal or a blocked bulkhead drain
- Ambient light sensor wiring damaged where it runs up the A pillar or across the top of the dash
- Wire pinched during dashboard, audio or airbag related work
- Corroded connector at the switch, with green deposits bridging adjacent pins
- Failed input circuit inside the body control module
How to fix it
- Watch the autolamp input status on live data while moving the light switch through every position
- Disconnect the headlamp switch and see whether the input state changes; if the fault stays, the wiring or the module is at fault
- Inspect the switch for signs of spilled liquid and check its connector for corrosion and bridged pins
- With the switch disconnected, measure the resistance between the input wire and ground; a low value proves a short to ground
- Follow the harness behind the dashboard and along the steering column, checking for chafing and trapped sections
- Check the ambient light sensor and its wiring for water damage where it runs up the pillar
- Repair or replace the damaged wiring or the switch, then confirm the headlamps respond correctly in every switch position and switch off with the ignition