Pinpoint Test R: The Parking, Rear Or License Plate Lamps Are On Continuously

Parking, Rear and License Plate Lamps

Pinpoint Test R: The Parking, Rear Or License Plate Lamps Are On Continuously

Refer to Wiring Diagram Set 92, Parking, Rear and License Lamps for schematic and connector information. [1][2]Diagrams By Number

Normal Operation

The Smart Junction Box (SJB) monitors the parking lamp request input from the headlamp switch. The SJB (Smart Junction Box) provides a ground for the parking lamp relay coil (integrated into the SJB (Smart Junction Box)) when a request for the parking lamps is received. When the parking lamp relay is energized, voltage is routed to the front and rear parking lamps.

- DTC B1578 (Lamp Park Input Circuit Short to Ground)- an on-demand DTC that may set when the SJB (Smart Junction Box) detects a short to ground from the parking lamps on input circuit.

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors

- Headlamp switch

- SJB (Smart Junction Box)

PINPOINT TEST R : THE PARKING, REAR OR LICENSE PLATE LAMPS ARE ON CONTINUOUSLY

R1 USE THE RECORDED DTCs FROM THE SJB (Smart Junction Box) SELF-TEST

- Check the recorded results from the SJB (Smart Junction Box) self-test.

Is DTC B1578 present?

Yes
GO to R2.

No
GO to R4.

R2 CHECK FOR A VOLTAGE SIGNAL TO THE HEADLAMP SWITCH

- Ignition OFF.

- Disconnect: Headlamp Switch C205.

- Measure the voltage between the headlamp switch C205-2, circuit CLS34 (GY), harness side and ground.





Is the voltage greater than 10 volts?

Yes
INSTALL a new headlamp switch. REFER to Headlamp Switch . CLEAR the DTCs. REPEAT the self-test.

No
GO to R3.

R3 CHECK CIRCUIT CLS34 (YE/OG) FOR A SHORT TO GROUND

- Disconnect: SJB (Smart Junction Box) C2280B.

- Measure the resistance between the headlamp switch C205-2, circuit CLS34 (GY), harness side and ground.





Is the resistance greater than 10,000 ohms?

Yes
GO to R5.

No
REPAIR circuit CLS34 (GY) for a short to ground. CLEAR the DTCs. REPEAT the self-test.

R4 CHECK THE SJB (Smart Junction Box) PARKING LAMPS OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE

- Ignition OFF.

- Disconnect: SJB (Smart Junction Box) C2280E.

- Ignition ON.

Do the parking lamps continue to illuminate?

Yes
REPAIR circuit CLS30 (VT/WH) for a short to voltage. TEST the system for normal operation.

No
GO to R5.

R5 CHECK FOR CORRECT SJB (Smart Junction Box) OPERATION

- Disconnect all the SJB (Smart Junction Box) connectors.

- Check for:
- corrosion

- damaged pins

- pushed-out pins


- Connect all the SJB (Smart Junction Box) connectors and make sure they seat correctly.

- Operate the system and verify the concern is still present.

Is the concern still present?

Yes
INSTALL a new SJB (Smart Junction Box). TEST the system for normal operation.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test.