• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
Back Up Lamp Signal Circuit | 2 | 2 | 1 | -- |
Back Up Lamp Control Circuit | 2 | 2 | -- | -- |
PNP Switch | 2 | 2 | 1 | -- |
1. Back Up Lamps Always ON 2. Back Up Lamps Inoperative |
The Park/Neutral Position (PNP) switch controls the supply voltage for the back up lamps. When the gear shifter is in the reveres position the PNP switch is closed and power is supply to the backup lamps.
The following conditions may cause a malfunction to occur:
• | stuck closed transaxle reveres switch |
• | The back up lamp bulbs voltage supply circuit shorted to voltage |
Master Electrical Component List
Ignition ON engine OFF, turn the back up lamps ON and OFF by placing the gear shifter from Park to Reverse back to Park, while observing the back up lamps, the back up lamps should turn on when the gear shifter is in reverse.
⇒ | If the test lamp does not illuminate, repair the voltage supply circuit for a short to ground or an open/high resistance. If the voltage supply circuit fuse is open, also test the signal circuit for a short to ground. |
⇒ | If the backup lamps are not OFF, test the signal circuit for a short to voltage. |
⇒ | If the backup lamps are not ON, test the signal circuit for an open/high resistance. |
⇒ | If less than infinite resistance, replace the PNP switch. |
⇒ | If greater than 2.1 ohms, replace the PNP switch. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.