Dodge Ram Truck 1500-2500-3500. Manual — part 960

P1573-BRAKE PEDAL STUCK OFF (CONTINUED)

6.

PCM

NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal
push out. Repair as necessary.
Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and
Ground circuits.

Were there any problems found?

Yes

>> Repair as necessary.

Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

No

>> Replace and program the Powertrain Control Module per Service Information.

Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

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ENGINE - ELECTRICAL DIAGNOSTICS - 3.7L/4.7L/5.7L

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P1593-SPEED CONTROL SWITCH 1/2 STUCK

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ENGINE - ELECTRICAL DIAGNOSTICS - 3.7L/4.7L/5.7L

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P1593-SPEED CONTROL SWITCH 1/2 STUCK (CONTINUED)

For the Engine circuit diagram (Refer to 9 - ENGINE - SCHEMATICS AND DIAGRAMS).

For a complete wiring diagram Refer to Section 8W.

•

When Monitored:
Ignition on.

•

Set Condition:
One of the S/C Switches is mechanically stuck in the On/Off, Resume/Accel, or Set position for too long. One
trip fault.

Possible Causes

(V37) S/C SWITCH NO.1 SIGNAL CIRCUIT OPEN

(V38) S/C SWITCH NO.2 SIGNAL CIRCUIT OPEN

(V937) SWITCH RETURN CIRCUIT OPEN

(V37) S/C SWITCH NO.1 SIGNAL CIRCUIT SHORTED TO BATTERY VOLTAGE

(V38) S/C SWITCH NO.2 SIGNAL CIRCUIT SHORTED TO BATTERY VOLTAGE

(V37) S/C SWITCH NO.1 SIGNAL CIRCUIT SHORTED TO GROUND

(V38) S/C SWITCH NO.2 SIGNAL CIRCUIT SHORTED TO GROUND

(V37) S/C SWITCH NO.1 SIGNAL CIRCUIT SHORTED TO THE (V937) S/C SWITCH RETURN CIRCUIT

(V38) S/C SWITCH NO.2 SIGNAL CIRCUIT SHORTED TO THE (V937) S/C SWITCH RETURN CIRCUIT

SPEED CONTROL SWITCH

PCM

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING).

Diagnostic Test

1.

SPEED CONTROL SWITCH NO.1 STUCK

Start the engine.

With a scan tool, monitor each switch function for the Speed Control Switches.

Press and release each Speed Control Button.

Is Switch No.1 Stuck?

Yes

>> Replace the Speed Control Switch.

Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

No

>> Go To 2

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ENGINE - ELECTRICAL DIAGNOSTICS - 3.7L/4.7L/5.7L

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P1593-SPEED CONTROL SWITCH 1/2 STUCK (CONTINUED)

2.

SPEED CONTROL SWITCH STATUS

Start the engine.

With a scan tool, monitor each switch function for the Speed Control Switches.

Press and release each Speed Control Button.

- Resume/Accel

- Cancel

- Decel (Coast)

- On/Off

- Set

Does each switch function change status when pressing and releasing each switch?

Yes

>> Refer to the INTERMITTENT CONDITION Diagnostic Procedure.

Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

No

>> Go To 3

3.

SPEED CONTROL SWITCHES

Turn the ignition off.

Remove the Speed Control Switches from the steering wheel.

Measure the resistance across each Speed Control Switch.

Monitor the ohmmeter while pressing each function button on each switch.

The following resistance specs are taken between terminals (V38) S/C Switch No.2 Signal and (V937) S/C Switch
Return circuit of the Switch when holding the switch button in the following position.

On/Off - 8.87 kohms

Set - 0.825 kohms

Coast - 0.47 kohms

Cancel - 3.92 kohms

Resume/Accel - 1.87 kohms

The following resistance specs are taken between terminals (V37) S/C Switch No.1 Signal and (V937) S/C Switch
Return circuits of the Switch when holding the switch button in the following position

On/Off - 0.47 kohms

Set - 5.49 kohms

Coast - 2.94 kohms

Cancel - 1.24 kohms

Resume/Accel - 15.4 kohms

Does the function on the Speed Control Switches have the correct resistance value?

Yes

>> Go To 4

No

>> Replace the Speed Control Switch that had the incorrect resistance value.

Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

DR/DH

ENGINE - ELECTRICAL DIAGNOSTICS - 3.7L/4.7L/5.7L

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