Light Failure Sensor Circuit
NOTE:
Light failure sensor may also be known as light failure relay.
Disconnect 12-pin harness connector from light failure sensor. Check circuit values between ground and terminals on vehicle harness side of connector. See Fig 1. Ensure circuit values are as specified. See LIGHT FAILURE SENSOR CIRCUIT VALUES table. If circuit values are as specified, replace light failure sensor. If circuit values are not as specified, check and repair related components or wiring harness as necessary. See COMPONENT TESTS . See WIRING DIAGRAMS .
LIGHT FAILURE SENSOR CIRCUIT VALUES
| Tester Connection | Condition | Circuit Value | ||
|---|---|---|---|---|
| 1 & Ground | Constant | (1) Continuity | ||
| 2 & Ground | Constant | (1) Continuity | ||
| 3 & Ground | Light Control Switch In OFF Position | No Voltage | ||
| 3 & Ground | Light Control Switch In TAIL Or HEAD Position | Battery Voltage | ||
| 4 & Ground | Ignition Switch In LOCK Or ACC Position | No Voltage | ||
| 4 & Ground | Ignition Switch In ON Position | Battery Voltage | ||
| 7 & Ground | Stoplight Switch In OFF Position | No Voltage | ||
| 7 & Ground | Stoplight Switch In ON Position | Battery Voltage | ||
| 8 & Ground | Ignition Switch In LOCK Or ACC Position | No Voltage | ||
| 8 & Ground | Ignition Switch In ON Position | Battery Voltage | ||
| 9 & Ground | Constant | (1) Continuity | ||
| 11 & Ground | Constant | Continuity | ||
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