Pinpoint Test L: The Stoplamps Are On Continuously
Stoplamps
Pinpoint Test L: The Stoplamps Are On Continuously
Refer to Wiring Diagram Set 90, Turn Signal/Stop/Hazard Lamps for schematic and connector information. [1][2]Diagrams By Number
Normal Operation
When the brake pedal is applied, the stoplamp switch routes voltage to the LH and RH rear stoplamps (MKZ), the Smart Junction Box (SJB) , the high mounted stoplamp and the PCM.
For Fusion, when the SJB (Smart Junction Box) detects the brake pedal is applied, the SJB (Smart Junction Box) provides voltage to the LH and RH rear stoplamps.
- DTC B1485 (Brake Pedal Input Short to Battery)- an on-demand DTC that sets when the SJB (Smart Junction Box) detects a short to voltage from the stoplamp switch input circuit.
- DTC B2045 (Left Rear Stop Lamp Circuit Open)- an on-demand DTC that sets when the SJB (Smart Junction Box) detects a short to voltage from the LH rear stop/turn lamp output circuit.
- DTC B2047 (Right Rear Stop Lamp Circuit Open)- an on-demand DTC that sets when the SJB (Smart Junction Box) detects a short to voltage from the RH rear stop/turn lamp output circuit.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Stoplamp switch
- PCM
- SJB (Smart Junction Box)
PINPOINT TEST L : THE STOPLAMPS ARE ON CONTINUOUSLY
L1 DETERMINE IF ALL THE STOPLAMPS ARE ILLUMINATED
- Ignition OFF.
- Observe the stoplamps with the brake pedal released.
Are all of the stoplamps illuminated?
Yes
GO to L3.
No
GO to L2.
L2 CHECK THE SJB (Smart Junction Box) STOPLAMP OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE
- Disconnect: SJB (Smart Junction Box) C2280D.
Do the stoplamps continue to illuminate?
Yes
If the LH rear lamp continues to illuminate, REPAIR circuit CLS18 (GY/BN) for a short to voltage. CLEAR the DTCs. REPEAT the self-test.
If the RH rear lamp continues to illuminate, REPAIR circuit CLS19 (VT/OG) for a short to voltage. CLEAR the DTCs. REPEAT the self-test.
No
GO to L7.
L3 CHECK THE STOPLAMP SWITCH
- Disconnect: Stoplamp Switch C278.
Do the stoplamps continue to illuminate?
Yes
GO to L4.
No
INSTALL a new stoplamp switch. REFER to Stoplamp Switch . CLEAR the DTCs. REPEAT the self-test.
L4 CHECK THE PCM
- Disconnect: PCM C175B.
Do the stoplamps continue to illuminate?
Yes
GO to L5.
No
GO to L6.
L5 CHECK THE STOPLAMP SWITCH OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE
- Disconnect: SJB (Smart Junction Box) C2280B.
Does the high mounted stoplamp continue to illuminate?
Yes
REPAIR circuit CCB08 (VT/WH) for a short to voltage. CLEAR the DTCs. REPEAT the self-test.
No
GO to L7.
L6 CHECK FOR CORRECT PCM OPERATION
- Disconnect all the PCM connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the PCM 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 PCM. 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.
L7 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.