What does it mean?
C1102 is a Chassis (ABS, traction control, steering) fault code. It indicates: Battery Voltage Low .
Symptoms
- ABS and stability control lamps come on during cranking or right after start up
- Slow cranking, dim lights and a clicking starter
- Several modules store low voltage codes at the same time
- Warning lamps go out and the fault clears after a longer drive
- Electric accessories reset or behave oddly
- The fault is worse in cold weather
Likely causes
- Discharged, aged or undersized battery that cannot hold voltage under load
- Corroded or loose battery terminals and main ground straps
- Charging fault such as a slipping belt, worn alternator or failed regulator
- High resistance in the module feed, often at a fuse box terminal or an inline connector
- Poor module ground point, rusted body stud or damaged ground wire
- Parasitic drain that flattens the battery overnight
- Repeated short trips that never allow the battery to recharge fully
How to fix it
- Load test the battery and check its state of charge before any other measurement
- Clean and tighten battery terminals, main earth straps and the module ground point
- Measure charging voltage at idle and with the electrical load switched on
- Check the drive belt tension and condition
- Perform voltage drop tests along the module feed, from the battery through the fuse box
- Test for a parasitic drain if the battery keeps going flat
- Clear the codes after the supply is stable and confirm the fault does not return