Chart A3 - History Code Diagnosis: Description
When ignition is first turned on, system voltage is applied through fuse No. 6 to REDUNDANT INDICATOR IGNITION 1 input and INFLATABLE RESTRAINT indicator light, which is connected to SIR INDICATOR output. Fuse No. 7 also applies system voltage to IGNITION 1 inputs. DERM responds by flashing INFLATABLE RESTRAINT indicator 7-9 times.
When engine is being cranked, system voltage is applied to DERM at CRANK input. DERM grounds light circuit until system voltage is removed from CRANK input. This results in a steady INFLATABLE RESTRAINT indicator during cranking. After cranking, DERM again flashes INFLATABLE RESTRAINT indicator 7 times, with solid on of indicator during crank counting as one.
NOTE:
Test numbers refer to test numbers on diagnostic chart. For circuit number identification, see WIRING DIAGRAMS.
WARNING:
To avoid air bag deployment while troubleshooting the 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.
- Checks for intermittent open and poor connections in DRIVER SENSE LOW circuit between steering column connector and passenger compartment discriminating sensor.
- Checks for intermittent open and poor connections in DRIVER 36VLR and PASSENGER 36VLR circuits between DERM and dual pole arming sensor.
- Checks for intermittent open and poor connections in ignition circuit that feeds dual pole arming sensor.
- Checks for intermittent open and poor connections in DRIVER SENSE LOW circuit and ground circuit that is connected to each discriminating sensor.
- Checks for an intermittent short to ground or short to voltage in both DRIVER 36VLR and PASSENGER 36VLR circuits. Also checks for intermittent short between DRIVER 36VLR and PASSENGER 36VLR circuits.
- Checks for intermittent open, short to ground, short to voltage or poor connection in DRIVER SOURCE SENSE and PASS SOURCE SENSE circuits.