Circuit/System Testing
IMPORTANT:
It is recommended that Component Testing be performed before Circuit Testing when diagnosing steering wheel controls.
CAUTION:
Refer to SIR Caution
.
- Ignition OFF, disconnect the harness connector at the right steering wheel control switch.
- Ignition ON, Radio ON, test for 8.5-10.5 volts between the 10-volt reference circuit terminal 1 and ground.
- If less than the specified value, test the 10-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the radio.
- If greater than the specified value, test the 10-volt reference for a short to voltage. If the circuit tests normal, replace the radio.
- Test for 8.5-10.5 volts between the 10-volt reference circuit terminal 1 and signal circuit terminal 4.
- If less than 8.5 volts, test the signal circuit for an open/ high resistance. If the circuit test normal, replace the radio.
- If greater than 10.5 volts, test the signal circuit for short to voltage. If the circuit test normal, replace the radio.
- Install a 3A fused jumper wire between the 10-volt reference circuit terminal 1 and the signal circuit terminal 5.
- Disconnect the harness connector at left steering wheel control switch.
- Test for 8.5-10.5 volts between the signal circuit terminal 1 and ground.
- If less than the specified value, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the radio.
- If greater than the specified value, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.
- Test for 8.5-10.5 volts between the signal circuit terminal 1and the signal circuit terminal 4.
- If less than the specified value, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the radio.
- If greater than the specified value, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.
- Ignition OFF, disconnect the C1 harness connector at the radio.
- Test for infinite resistance between the signal circuit terminal 11 and ground.
- If less than the specified value, test the signal circuit for a short to ground.
- If all circuits test normal, test or replace switch.