SRS Warning Lamp Flickers, Intermittently or is Constantly Lit

Complaint: RS or SRS warning lamp flickers, lights up intermittently or shines constantly.

Cause/Remedy:
1. Film of grease on collector ring in steering wheel. Clean collector ring thoroughly (behind the tracks as well). Wash down with cleaning benzine, blast with air and rub dry using a fuzz-free cloth; install new collector ring if necessary.
2. "Cold soldering point" on cable harness. Check cable harness using tester or with socket box and multimeter (as of 09/87) whilst moving cable harness plug connection. Test values must remain constant.
Resolder cable correctly.
3. Plug sleeves of plug connections stretched producing insufficient contact with relevant components.
Move 10-pin plug connection (X29/9) during the test cycle (10 s or 4 s as of 09/87) of the RS or SRS warning lamp (A1e15). Warning lamp must not light up. Connect tester or socket box and multimeter (as of 09/87) and move plug connections.
Test values must remain constant.
Renew plug sleeves.
4. Bolts on positive or negative connections of airbag cable harness loose.
Tighten bolts.
5. Insufficient press-on force of carbon contacts.
Check smoothness of carbon contacts. Renew carbon contacts if necessary.
6. Voltage transformer (N24) faulty (only in vehicles up to 09/87).
Disconnect voltage transformer connection (built-in fault detection). If warning lamp goes out renew voltage transformer.
For test step 2, the test value must remain constant for at least 30 s.
Renew voltage transformer if necessary.
7. Reserve power source (C1) faulty (only in vehicles up to 09/87).
Check reserve power source using tester (reference value). Renew reserve power source if necessary.
8. Control unit (N2/2) faulty.
Connect control unit and check airbag and belt tensioner system by means of RS or SRS warning lamp. Renew control unit if necessary.
9. Airbag unit or belt tensioner unit triggered. Renew parts.

The following points only apply for vehicles as of 09/87.
10. If pulse display 10 appears (airbag not triggered).
Renew control unit and attach additional ground cable shoe from airbag cable harness to lowest point.
11. Check cable to test coupling for diagnosis, 8-pin (X92), socket 6, for short to ground. Renew cable.
12. Plug connection for driver's or passenger's belt buckle not connected.
Connect plug connection.
13. Undervoltage. Check power supply (11-14 V).
Check battery and alternator.
14. Open circuit in cables to collector rings (X28/4 - collector rings).
Renew collector rings.
15. Intermittent or constant short to ground in cable to test coupling for diagnosis (X92), socket 6, at battery frame. Renew cable. Deburr battery frame.
16. Wrong control unit installed (airbag 1/3). Renew control unit.