Pinpoint Test E: The Low Beam(s) Are Always On
Headlamps
Pinpoint Test E: The Low Beam(s) Are Always On
Normal Operation
The Smart Junction Box (SJB) sends voltage signals to the headlamp switch to monitor the OFF PARKING LAMPS and HEADLAMPS position. At any given time, the headlamp switch routes one of the input circuits to ground.
When the SJB (Smart Junction Box) detects the headlamp switch in the HEADLAMPS ON position, the SJB (Smart Junction Box) provides voltage to the LH and RH ballasts.
The High Intensity Discharge (HID) headlamps utilize a second (hot at all times) voltage feed to the HID (High Intensity Discharge) ballasts.
When the ballasts are provided voltage from the SJB (Smart Junction Box), the ballasts provide high voltage to the HID (High Intensity Discharge) bulbs.
If the SJB (Smart Junction Box) detects a concern with any of the headlamp switch inputs for 5 seconds (multiple headlamp switch inputs active at the same time or no inputs active), the SJB (Smart Junction Box) turns the exterior lamps on.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Headlamp switch
- Ballast
- SJB (Smart Junction Box)
PINPOINT TEST E : THE LOW BEAM(S) ARE ALWAYS ON
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
E1 CHECK FOR AUTOLAMP DTCs
- Review the DTCs retrieved from the SJB (Smart Junction Box) self-test.
Is DTC B1696, B1791, B1793 or B2008 present?
Yes
GO to Pinpoint Test J Pinpoint Test J: The Autolamps Are On Continuously.
No
GO to E2.
E2 CHECK THE SJB (Smart Junction Box) AUTOLAMP ON REQUEST PID
- Enter the following diagnostic mode on the scan tool: SJB (Smart Junction Box) DataLogger.
- While placing the headlamp switch in the AUTOLAMPS ON and then OFF position, monitor the SJB (Smart Junction Box) headlamp switch PID (HDLMP_AUT_CKT).
Does the PID indicate ON with the headlamp switch in the AUTOLAMPS ON position and OFF when the headlamp switch is in the OFF position?
Yes
GO to E3.
No
GO to Pinpoint Test J Pinpoint Test J: The Autolamps Are On Continuously.
E3 CHECK THE SJB (Smart Junction Box) HEADLAMP SWITCH PIDs
NOTE: Make sure the headlamp switch is lined up in the correct position when monitoring the PIDs.
NOTE: Only one PID should indicate ON at each headlamp switch position.
- Enter the following diagnostic mode on the scan tool: SJB (Smart Junction Box) DataLogger.
- While moving the headlamp switch through all positions, monitor the SJB (Smart Junction Box) headlamp switch input PIDs (HDLMP_OFF_CKT, HDLMP_PRK_CKT, HDLMP_ON_CKT).
Do the headlamp switch positions agree with the PIDs (with only one PID indicating ON in each position)?
Yes
GO to E8.
No
GO to E4.
E4 CHECK FOR VOLTAGE TO THE HEADLAMP SWITCH
- Ignition OFF.
- Disconnect: Headlamp Switch C205.
- Measure the voltage between the headlamp switch, harness side and ground as follows:
Headlamp Switch Connector-Pin Circuit C205-9 CLF23 (WH/VT) C205-5 CLS34 (GY) C205-10 CLF29 (BN)
Are the voltages greater than 10 volts?
Yes
GO to E5.
No
GO to E6.
E5 CHECK FOR VOLTAGE TO THE HEADLAMP SWITCH USING THE CONNECTOR GROUND
- Measure the voltage between headlamp switch C205-9, circuit CLF23 (WH/VT), harness side and the headlamp switch C205-7, circuit GD116 (BK/VT), harness side.
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
REPAIR circuit GD116 (BK/VT) for an open. CLEAR the DTCs. REPEAT the self-test.
E6 CHECK THE HEADLAMP SWITCH INPUT CIRCUITS FOR A SHORT TO GROUND
- Disconnect: SJB (Smart Junction Box) C2280B.
- Measure the resistance between the headlamp switch, harness side and ground as follows:
Headlamp Switch Connector-Pin Circuit C205-9 CLF23 (WH/VT) C205-5 CLS34 (GY) C205-10 CLF29 (BN)
Are the resistances greater than 10,000 ohms?
Yes
GO to E7.
No
REPAIR the circuit in question for a short to ground. CLEAR the DTCs. REPEAT the self-test.
E7 CHECK THE HEADLAMP SWITCH INPUT CIRCUITS FOR AN OPEN
- Measure the resistance between the headlamp switch, harness side and the SJB (Smart Junction Box), harness side as follows:
Headlamp Switch Connector-Pin SJB (Smart Junction Box) Connector-Pin Circuit C205-9 C2280B-47 CLF23 (WH/VT) C205-5 C2280B-31 CLS34 (GY) C205-10 C2280B-30 CLF29 (BN)
Are the resistances less than 5 ohms?
Yes
GO to E10.
No
REPAIR the circuit in question for an open. CLEAR the DTCs. REPEAT the self-test.
E8 CHECK THE SJB (Smart Junction Box) OUTPUT
- Ignition OFF.
- Disconnect: SJB (Smart Junction Box) C2280E.
- Ignition ON.
Does the LH or RH headlamp continue to illuminate?
Yes
GO to E9.
No
GO to E10.
E9 CHECK THE SJB (Smart Junction Box) LOW BEAM OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: Illuminated Headlamp.
- Ignition ON.
- Measure the voltage between the LH headlamp C1021-8, circuit CLF04 (BN/BU), harness side and ground; or between the RH headlamp C1041-8, circuit CLF05 (BU/GN), harness side and ground.
Is any voltage present?
Yes
REPAIR the circuit in question for a short to voltage. CLEAR the DTCs. REPEAT the self-test.
No
INSTALL a new ballast. REFER to Ballast . TEST the system for normal operation.
E10 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.