DODGE RAM SRT-10 2006 Service Repair Manual

P1593-SPEED CONTROL SWITCH 1/2 STUCK
For a complete wiring diagramRefer 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?
Ye s>>
Replace the Speed Control Switch.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 2
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?
Ye s>>
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?
Ye s>>
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)
4.(V37) S/C SWITCH NO.1 SIGNAL CIRCUIT SHORTED TO BATTERY VOLTAGE
Turn the ignition off.
Disconnect the C3 PCM harness connector.
Ignition on, engine not running.
Measure the voltage of the (V37) S/C Switch No.1 Signal circuit in the
S/C Switch harness connector.
Is the voltage above 5.0 volts?
Ye s>>
Repair the short to voltage in the (V37) S/C Switch No.1
Signal circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 5

5.(V38) S/C SWITCH NO.2 SIGNAL CIRCUIT SHORTED TO BATTERY VOLTAGE
Measure the voltage of the (V38) S/C Switch No.2 Signal circuit in the
S/C Switch harness connector.
Is the voltage above 5.0 volts?
Ye s>>
Repair the short to voltage in the (V38) S/C Switch No.2
Signal circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 6
6.(V37) S/C SWITCH NO.1 SIGNAL CIRCUIT OPEN
Turn the ignition off.
CAUTION: Do not probe the PCM harness connectors. Probing the
PCM harness connectors will damage the PCM terminals resulting
in poor terminal to pin connection. Install Miller Special Tool #8815
to perform diagnosis.
Measure the resistance of the (V37) S/C Switch No.1 Signal circuit from
both Speed Control harness connectors to the appropriate terminals of
special tool #8815.
Is the resistance below 5.0 ohms for both measurements?
Ye s>>
Go To 7
No>>
Repair the open in the (V37) S/C Switch No.1 Signal circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)

7.(V38) S/C SWITCH NO.2 SIGNAL CIRCUIT OPEN
Measure the resistance of the (V38) S/C Switch No.2 Signal circuit from
both Speed Control harness connectors to the appropriate terminals of
special tool #8815.
Is the resistance below 5.0 ohms for both measurements?
Ye s>>
Go To 8
No>>
Repair the open in the (V38) S/C Switch No.2 Signal circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
8.(V937) SWITCH RETURN OPEN
NOTE: The measurement must be taken from both Speed Control
Switch harness connectors.
Measure the resistance of the (V937) Switch Return circuit from the
Speed Control harness connector to the appropriate terminal of special
tool #8815.
Is the resistance below 5.0 ohms for both measurements?
Ye s>>
Go To 9
No>>
Repair the open in the (V937) Switch Return circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)

9.(V37) S/C SWITCH NO.1 SIGNAL CIRCUIT SHORTED TO GROUND
Measure the resistance between ground and the (V37) S/C Switch No.1
Signal circuit in the Speed Control harness connector.
Istheresistancebelow100ohms?
Ye s>>
Repair the short to ground in the (V37) S/C Switch No.1
Signal circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 10
10.(V38) S/C SWITCH NO.2 SIGNAL CIRCUIT SHORTED TO GROUND
Measure the resistance between ground and the (V38) S/C Switch No.2
Signal circuit in the Speed Control harness connector.
Istheresistancebelow100ohms?
Ye s>>
Repair the short to ground in the (V38) S/C Switch No.2
Signal circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 11

11 .(V37) S/C SWITCH NO.1 SIGNAL CIRCUIT SHORTED TO THE (V937) SWITCH RETURN CIRCUIT
Measure the resistance between the (V37) S/C Switch No.1 Signal cir-
cuit and the (V937) Switch Return circuit in the Speed Control harness
connector.
Is the resistance below 5.0 ohms?
Ye s>>
Repair the short between the (V937) Switch Return circuit
and the (V37) S/C Switch No.1 Signal circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 12
12.(V38) S/C SWITCH NO.2 SIGNAL CIRCUIT SHORTED TO THE (V937) SWITCH RETURN CIRCUIT
Measure the resistance between the (V38) S/C Switch No.2 Signal cir-
cuit and the (V937) Switch Return circuit in the Speed Control harness
connector.
Is the resistance below 5.0 ohms?
Ye s>>
Repair the short between the (V937) Switch Return circuit
and the (V38) S/C Switch No.2 Signal circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 13

13.SPEED CONTROL SWITCH VOLTAGE VALUES
Allow the engine to idle.
With a scan tool, monitor the S/C Switch voltage readings.
SWITCH POSITION SWITCH No.1 VOLTAGE VALUE SWITCH No.2 VOLATGE VALUE
NO SWITCHES PRESSED 4.31 to 4.78 volts 4.31 to 4.78 volts
ON/OFF PRESSED 0.59 to 1.13 volts 3.53 to 3.92 volts
RES/ACCEL PRESSED 3.88 to 4.17 volts 2.04 to 2.47 volts
SET PRESSED 3.16 to 3.56 volts 1.17 to 1.56 volts
COAST PRESSED 2.57 to 2.94 volts 0.77 to 1.09 volts
CANCEL PRESSED 1.59 to 1.99 volts 2.84 to 3.25 volts

Take these same voltage measurements with a voltmeter by back probing the (V37) S/C Switch No.1 Signal circuit
and the (V38) S/C Switch No.2 Signal circuit at the switches.
Compare the voltage readings on the voltmeter to what the scan tool displayed.
Are the voltage readings out of the listed specification and do you less than a 0.2 of a volt difference
between the voltmeter switch values and the scan tool switch value?
Ye s>>
Replace the Speed Control Switch.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 14
14.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?
Ye s>>
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)

P1593-SPEED CONTROL SWITCH 1 STUCK (3.7L, 4.7L)
For a complete wiring diagramRefer to Section 8W.