What does it mean?
B1203 is a Body (airbags, seat belts, body electronics) fault code. It indicates: SRS Warning Indicator Circuit/Performance .
Symptoms
- SRS warning lamp does not perform its bulb check when the ignition is switched on
- SRS lamp stays on permanently, or flickers
- No airbag warning shown even though other restraint faults are stored
- Other cluster telltales may behave oddly at the same time
- Vehicle fails a safety inspection because the airbag lamp does not self test
Likely causes
- Burnt-out warning bulb, failed LED, or a bulb removed from the cluster
- Open, shorted or high-resistance wire between the restraint module and the instrument cluster
- Corroded, loose or partially seated connector at the cluster or at the restraint module
- Instrument cluster fault, or the cluster has lost communication with the restraint module
- Deliberate tampering: a resistor fitted or the lamp circuit cut to hide an existing airbag fault
- Poor supply or ground at the cluster
- Failed lamp driver output inside the restraint control module
How to fix it
- Switch the ignition on and watch whether the SRS lamp completes its normal self test sequence
- Read both the restraint module and the cluster and note any lost communication codes
- Check the warning bulb or LED and its circuit continuity between the cluster and the module
- Inspect both connectors for corrosion, spread terminals and previous repairs
- Look for tampering: added resistors, cut wires or non-original splices in the lamp circuit
- Verify cluster supply voltage and ground quality
- Repair the circuit, or replace the cluster if its lamp driver is faulty; replace and configure the restraint module only after the wiring and cluster are proven good