Pinpoint Tests

Daytime Running Lamps (DRL)

Pinpoint Tests

Pinpoint Test AE: The Daytime Running Lamps (DRL) Are Inoperative

Normal Operation

When the ignition switch is in the RUN position, the headlamps are not on (from the autolamp system or manual control from the headlamp switch) and the transmission is not in PARK (P), the Smart Junction Box (SJB) provides a pulse-width modulated voltage to the low beam headlamps. This illuminates the headlamps at a reduced intensity.

This pinpoint test is intended to diagnose the following:

- Exterior lighting system input/output
- Ignition switch input
- Transmission gear input
- SJB



PINPOINT TEST AE: THE DRL ARE INOPERATIVE

-------------------------------------------------
AE1 VERIFY THE DRL OPERATION


- Ignition ON.
- Place the headlamp switch in the OFF position.
- Place the gear selector lever in any gear other than PARK (P).
- Are the DRL illuminated?

Yes
The system is operating correctly. INFORM the customer of the conditions required for the DRL to operate correctly.

No
GO to AE2.

-------------------------------------------------
AE2 CHECK THE OPERATION OF THE HEADLAMPS


- Place the headlamp switch in the HEADLAMPS ON position and observe the headlamps.
- Do the headlamps operate correctly?

Yes
GO to AE3.

No
REFER to Headlamps Testing and Inspection.

-------------------------------------------------
AE3 CHECK THE IGNITION SWITCH INPUT


- Place the headlamp switch in the OFF position.
- Enter the following diagnostic mode on the scan tool: SJB DataLogger.
- Monitor the SJB ignition switch PIDs (IGN_A_ECU, IGN_O_ECU, IGN_R_ECU, IGN_S_ECU) while cycling the ignition switch through all its positions.
- Do the PIDs agree with the ignition switch positions?

Yes
GO to AE4.

No
REFER to Steering Column to diagnose the input from the ignition switch. Testing and Inspection

-------------------------------------------------
AE4 CHECK THE TRANSMISSION GEAR INPUT


- Enter the following diagnostic mode on the scan tool: PCM or TCM DataLogger.
- Monitor the PCM or TCM transmission gear status PID (TR) while placing the gear selector lever through all its positions.
- Does the PID agree with the gear selection?

Yes
INSTALL a new SJB. TEST the system for normal operation.

No
REFER to Transmission Control Systems to diagnose the transmission range input. Testing and Inspection

-------------------------------------------------