Pinpoint Test B: DTC P0504:00, P0572:00, P0573:00 Or P1703:00
Cruise Control
Pinpoint Test B: DTC P0504:00, P0572:00, P0573:00 Or P1703:00
Normal Operation
The stoplamp switch is a single plunger 2-stage switch with 2 inputs to the PCM. When the brake pedal is applied, the first stage, which is a normally open stoplamp switch, closes and sends a voltage signal to the PCM deactivating the cruise control, if engaged. The second stage is the normally closed cruise control deactivator switch (integral to the stoplamp switch), which opens and removes the ground signal (3.7L, 5.0L and 6.2L engine) or reference voltage (3.5L engine) to the PCM when the brake pedal is firmly applied. This is a redundant signal to the PCM. There is less than one millimeter in plunger travel between the first and second stage.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Stoplamp switch
- Cruise control deactivator switch (integral to the stoplamp switch)
- PCM
- ABS module
PINPOINT TEST B : DTC P0504:00, P0572:00, P0573:00 Or P1703:00
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
B1 CHECK THE OPERATION OF THE STOPLAMPS
- Ignition ON.
- Operate the stoplamps.
Do the stoplamps and high mounted stoplamp operate correctly?
Yes
GO to B2.
No
REFER to Lighting and Horns, to continue diagnosis of the stoplamps.
B2 CHECK THE STOPLAMP SWITCH (BOO1) AND CRUISE CONTROL DEACTIVATOR SWITCH (BOO2) PIDs
- Enter the following diagnostic mode on the scan tool: PCM DataLogger.
- Monitor the PCM PIDs BOO1 (stoplamp input) and BOO2 (cruise control deactivator switch) while applying and releasing the brake pedal as follows:
Brake Pedal Position BOO1 PID BOO2 PID Released Off Off Applied lightly On Off Applied firmly On On
Do the PID values agree with the brake pedal position?
Yes
GO to B7.
No
For an incorrect BOO1 PID value, GO to B3.
For an incorrect BOO2 PID value (3.5L engine), GO to B8.
For an incorrect BOO2 PID value (3.7L, 5.0L and 6.2L engines), GO to B4.
B3 CHECK THE STOPLAMP SWITCH CIRCUIT FOR VOLTAGE
- Ignition OFF.
- Disconnect: PCM C1551B (3.5L), C175B (3.7L) or PCM C1381B (5.0L/6.2L).
- Ignition ON.
- For 3.5L engine, while applying the brake pedal, measure the voltage between the PCM C1551B-66, circuit CCB08 (VT/WH), harness side and ground.
- For 3.7L, 5.0L and 6.2L engines, while applying the brake pedal, measure the voltage between the PCM C175B-13 (3.7L) or C1381B-13 (5.0L/6.2L), circuit CCB08 (VT/WH), harness side and ground.
Is the voltage greater than 10 volts with the brake pedal applied?
Yes
GO to B12.
No
REPAIR the circuit for an open. CLEAR the DTCs. REPEAT the self-test.
B4 CHECK THE CRUISE CONTROL DEACTIVATOR SWITCH FOR CORRECT OPERATION (3.7L, 5.0L and 6.2L)
- Disconnect: PCM C175B (3.7L) or PCM C1381B (5.0L/6.2L).
- While firmly applying and releasing the brake pedal, measure the resistance between the PCM C175B-46 (3.7L) or C1381B-46 (5.0L/6.2L), circuit CES09 (VT/OG), harness side and ground.
Is the resistance less than 5 ohms with the brake pedal released, and greater than 10,000 ohms with the brake pedal firmly applied?
Yes
GO to B12.
No
GO to B5.
B5 CHECK THE CRUISE CONTROL DEACTIVATOR SWITCH GROUND CIRCUIT FOR AN OPEN
- Ignition OFF.
- Disconnect: Stoplamp Switch C278.
- Measure the resistance between the stoplamp switch C278-2, circuit GD120 (BK/GN), harness side and ground.
Is the resistance less than 5 ohms?
Yes
GO to B6.
No
REPAIR the circuit for an open. CLEAR the DTCs. TEST the system for normal operation.
B6 CHECK THE CRUISE CONTROL DEACTIVATOR SWITCH SIGNAL CIRCUIT FOR A SHORT TO GROUND
- Measure the resistance between the stoplamp switch C278-3, circuit CES09 (VT/OG), harness side and ground.
Is the resistance less than 5 ohms?
Yes
GO to B7.
No
REPAIR the circuit for an open. CLEAR the DTCs. TEST the system for normal operation.
B7 CHECK THE CRUISE CONTROL DEACTIVATOR SWITCH SIGNAL CIRCUIT FOR AN OPEN
- Connect a fused jumper wire between the stoplamp switch C278-3, circuit CES09 (VT/OG), harness side and the stoplamp switch C278-2, circuit GD120 (BK/GN), harness side.
- Measure the resistance between the PCM C175B-46 (3.7L) or C1381B-46 (5.0L/6.2L), circuit CES09 (VT/OG), harness side and ground.
Is the resistance less than 5 ohms?
Yes
INSTALL a new stoplamp switch. CLEAR the DTCs. TEST the system for normal operation.
No
REPAIR circuit CES09 (VT/OG) for an open. CLEAR the DTCs. TEST the system for normal operation.
B8 CHECK THE CRUISE CONTROL DEACTIVATOR SWITCH FOR CORRECT OPERATION (3.5L)
- Ignition OFF.
- Disconnect: PCM C1551B.
- While firmly applying and releasing the brake pedal, measure the resistance between the PCM C1551B-93, circuit CES09 (VT/OG), harness side and the PCM C1551B-7, circuit RE407 (YE/VT), harness side.
Is the resistance less than 5 ohms with the brake pedal released, and greater than 10,000 ohms with the brake pedal firmly applied?
Yes
GO to B9.
No
GO to B10.
B9 CHECK THE CRUISE CONTROL DEACTIVATOR SWITCH CIRCUIT FOR A SHORT TO VOLTAGE
- Disconnect: Stoplamp Switch C278.
- Ignition ON.
- Measure the voltage between the PCM C1551B-93, circuit CES09 (VT/OG), harness side and ground; and the PCM C1551B-7, circuit RE407 (YE/VT), harness side and ground.
Is any voltage present?
Yes
REPAIR the circuit in question. CLEAR the DTCs. TEST the system for normal operation.
No
GO to B12.
B10 CHECK THE CRUISE CONTROL DEACTIVATOR SWITCH SIGNAL CIRCUIT FOR AN OPEN OR SHORT TO GROUND
- Ignition OFF.
- Measure the resistance between the PCM C1551B-93, circuit CES09 (VT/OG), harness side and the stoplamp switch C278-3, circuit CES09 (VT/OG) harness side; and the PCM C1551B-93, circuit CES09 (VT/OG), harness side and ground.
Is the resistance less than 5 ohms between the PCM and the stoplamp switch and greater than 10,000 ohms between the PCM and ground?
Yes
GO to B11.
No
REPAIR the circuit. CLEAR the DTCs. TEST the system for normal operation.
B11 CHECK THE CRUISE CONTROL DEACTIVATOR SWITCH SIGNAL RETURN CIRCUIT FOR AN OPEN
- Measure the resistance between the PCM C1551B-7, circuit RE407 (YE/VT), harness side and the stoplamp switch C278-2, circuit RE407 (YE/VT) harness side.
Is the resistance less than 5 ohms?
Yes
INSTALL a new stoplamp switch. CLEAR the DTCs. TEST the system for normal operation.
No
REPAIR the circuit. CLEAR the DTCs. TEST the system for normal operation.
B12 CHECK FOR CORRECT PCM OPERATION
- Connect: All Disconnected Connectors.
- 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.