Diagnostic Procedure

WARNING: This page is about a different car, the 2004 Dodge Pickup and 2004 Dodge Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Refer to VERIFICATION TESTS for appropriate verification test procedures.

Ignition on, engine not running.
With the DRBIII®, read DTCs and record the related Freeze Frame data.

NOTE: In the below step you will need to actuate both S/C solenoids separately. Note the operation of the each solenoid when actuated.

With the DRBIII®, actuate the Speed Control Vacuum Solenoid and note operation.

With the DRBIII®, actuate the Speed Control Vent Solenoid and note operation.

Choose the conclusion that best matches the solenoids operation.
1. Vacuum Solenoid not operating
  1. Go To 2
2. Vent Solenoid not operating
  1. Go To 5
3. Both S/C Solenoids not operating
  1. Go To 8
4. Both S/C Solenoids operating
  1. Go To 13
Turn the ignition off.
Disconnect the Speed Control Servo harness connector.

Ignition on, engine not running.

With the DRBIII®, actuate the Speed Control Vacuum Solenoid.

Using a 12-volt test light connected to 12-volts, probe the (V36) S/C Vacuum Sol Control circuit.

Does the test light illuminate brightly and flash?
1. Yes --> Replace the Speed Control Servo.
  Perform POWERTRAIN VERIFICATION TEST VER - 4 .
2. No --> Go To 3
Turn the ignition off.
Disconnect the PCM harness connectors.

Measure the resistance of the (V36) S/C Vacuum Sol Control circuit between the PCM harness connector and Speed Control Servo harness connector.

Is the resistance below 5.0 ohms?
1. Yes --> Go To 4
2. No --> Repair the open in the (V36) S/C Vacuum Sol Control circuit.
  Perform POWERTRAIN VERIFICATION TEST VER - 4 .
Measure the resistance between ground and the (V36) S/C Vacuum Sol Control circuit at the PCM harness connector.
Is the resistance below 100 ohms?
1. Yes --> Repair the short to ground in the (V36) S/C Vacuum Sol Control circuit.
  Perform POWERTRAIN VERIFICATION TEST VER - 4 .
2. No --> Go To 12
Turn the ignition off.
Disconnect the Speed Control Servo harness connector.

Ignition on, engine not running.

With the DRBIII®, actuate the S/C Vent Solenoid.

Using a 12-volt test light connected to 12-volts, probe the (V35) S/C Vent Sol Control circuit in the Speed Control Servo harness connector.

Does the test light illuminate brightly and flash?
1. Yes --> Replace the Speed Control Servo.
  Perform POWERTRAIN VERIFICATION TEST VER - 4 .
2. No --> Go To 6
Turn the ignition off.
Disconnect the PCM harness connectors.

Measure the resistance of the (V35) S/C Vent Sol Control circuit between the PCM harness connector and S/C Servo harness connector.

Is the resistance below 5.0 ohms?
1. Yes --> Go To 7
2. No --> Repair the open in the (V35) S/C Vent Sol Control circuit.
  Perform POWERTRAIN VERIFICATION TEST VER - 4 .
Measure the resistance between ground and the (V35) S/C Vent Sol Control circuit at the PCM harness connector.
Is the resistance below 100 ohms?
1. Yes --> Repair the short to ground in the (V35) S/C Vent Sol Control circuit.
  Perform POWERTRAIN VERIFICATION TEST VER - 4 .
2. No --> Go To 12
Turn the ignition off.
Disconnect the S/C Servo harness connector.

Ignition on, engine not running.

Turn the Cruise Control on.

Using a 12-volt test light connected to ground, probe the (V30) S/C Brake Switch Output circuit in the S/C Servo harness connector.

Does the test light illuminate brightly?
1. Yes --> Replace the Speed Control Servo.
  Perform POWERTRAIN VERIFICATION TEST VER - 4 .
2. No --> Go To 9
Turn the ignition off.
Disconnect the Brake Lamp Switch harness connector.

Measure the resistance of the (V30) S/C Brake Switch Output circuit from the S/C Servo harness connector to the Brake Lamp Switch harness connector.

Is the resistance below 5.0 ohms?
1. Yes --> Go To 10
2. No --> Repair the open in the (V30) S/C Brake Switch Output circuit.
  Perform POWERTRAIN VERIFICATION TEST VER - 4 .
Ignition on, engine not running.
Turn the Cruise Control on, it may be necessary to hold the On button down while checking the following circuit.

Using a 12-volt test light connected to ground, probe the (V32) S/C Power Supply circuit in the Brake Lamp Switch harness connector.

Does the test light illuminate brightly?
1. Yes --> Replace the Brake Lamp Switch.
  Perform POWERTRAIN VERIFICATION TEST VER - 4 .
2. No --> Go To 11
Turn the ignition off.
Disconnect the PCM harness connectors.

Measure the resistance of the (V32) S/C Power Supply circuit between the PCM harness connector and the Brake Lamp Switch harness connector.

Is the resistance below 5.0 ohms?
1. Yes --> Go To 12
2. No --> Repair the open in the (V32) S/C Supply circuit.
  Perform POWERTRAIN VERIFICATION TEST VER - 4 .

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.
If the there are no possible causes remaining, view repair.
1. Repair
  1. Replace and program the Powertrain Control Module per Service Information.
  2. Perform POWERTRAIN VERIFICATION TEST VER - 4 .
Turn the ignition off.
Disconnect the S/C Servo harness connector.

Using a 12-volt test light connected to 12-volts, probe the (Z10) Ground circuit in the S/C Servo harness connector.

Does the test light illuminate brightly?
1. Yes --> Refer to the SYMPTOM: INTERMITTENT CONDITION Symptom (Diagnostic Procedure).
  Perform POWERTRAIN VERIFICATION TEST VER - 4 .
2. No --> Repair the open in the (Z10) Ground circuit.
  Perform POWERTRAIN VERIFICATION TEST VER - 4 .