Chart B - Flash Code Diagnosis: Description
When ignition is first turned on, system voltage is applied from fuse No. 6 to SIR INDICATOR HIGH and INFLATABLE RESTRAINT indicator light, which is connected to SIR INDICATOR LOW. Fuse No. 7 applies system voltage to IGNITION 1 inputs A3 and B3. Diagnostic Energy Reserve Module (DERM) responds by flashing INFLATABLE RESTRAINT indicator 7-9 times.
When engine is cranked, system voltage is applied to DERM at CRANK input. DERM grounds lamp circuit until system voltage is removed from CRANK input. This results in a steady INFLATABLE RESTRAINT indicator during cranking. After engine is cranked, DERM will again flash INFLATABLE RESTRAINT indicator 7-9 times.
NOTE:
Test numbers refer to numbers on diagnostic chart. For circuit number identification, see WIRING DIAGRAMS.
WARNING:
To avoid air bag deployment while trouble shooting SIR system, only use test equipment specified in diagnostic charts. Under no circumstances should battery powered test equipment or test light be used. Carefully follow all instructions.
- If flash codes have been used to diagnose and repair a fault, codes diagnosed and repaired will still appear as history codes. History codes can only be cleared using a Scan tester.
- If diagnostic charts request clearing SIR codes, skip this step since codes cannot be cleared through flash code diagnostics.