P0595 code

[CPesce]

Does anyone have any info on p0595 code? i do know its low voltage on the cruise control servo. How do I keep from coming up and does it cause any issues with performance.

 

[p-Bar]

P0595 LOW VOLTAGE DETECTED AT THE S/C BRAKE SWITCH OUTPUT
When Monitored and Set Condition:

When Monitored: While the key is on.
Set Condition: The voltage detected on the Cruise Control Servo is above a calibrated value for a calibrated
amount on time.
POSSIBLE CAUSES

SPEED CONTROL SERVO
(V32) S/C 12-VOLT SOURCE CIRCUIT OPEN
GROUND CIRCUIT OPEN
(V32) S/C 12-VOLT SOURCE SHORTED TO VOLTAGE
(V32) S/C 12-VOLT SOURCE SHORTED TO OTHER CIRCUITS
ECM
INTERMITTENT CONDITION

DIAGNOSTIC PROCEDURE

Turn the ignition off. Disconnect the Speed Control Servo harness connector
NOTE: Check connectors - Clean/repair as necessary.
Turn the ignition on. With the DRBIII®, actuate the S/C 12 volt source. Using a 12-volt test light connected to ground, check the S/C 12-volt source circuit in the Speed Control Servo harness connector.
NOTE: The test light must illuminate brightly.
Compare the brightness to that of a direct connection to the battery. Does the test light cycle on and off and illuminate brightly?
Yes --> Go To 2
No --> Go To 3
Turn the ignition off. Disconnect the ECM harness connectors.
NOTE: Check connectors - Clean/repair as necessary.
Measure the resistance of the ground circuit between the Speed control servo connector and battery negative. Is the resistance less than 10 ohms?
Yes --> Replace the Speed control servo.
No --> Repair the open ground circuit at the Cruise control servo harness connector.
Turn the ignition off. Disconnect the ECM harness connectors.
NOTE: Check connectors - Clean/repair as necessary.
Measure the resistance of the S/C 12-volt source circuit between the ECM harness connector and the Speed Control servo assembly harness connector. Is the resistance less than 10 Ohms?
Yes --> Go To 4
No --> Repair the open (V32) 12-volt source circuit.
Measure the voltage between the S/C 12-volt source circuit in the Speed Control servo assembly harness connector and battery negative. Is the voltage greater than 1 volt?
Yes --> Repair the (V32) S/C 12-volt source circuit shorted to voltage.
No --> Go To 5
Measure the resistance between the S/C 12-volt source circuit in the ECM harness connector and all other circuits in the ECM harness connectors. Is the resistance less than 10 Ohms?
Yes --> Repair the (V32) S/C 12-volt source circuit shorted to other circuit.
No --> Go To 6
Reconnect the ECM harness connectors. Ignition on, engine not running. With the DRBIII®, actuate the S/C 12-volt source. Using a 12-volt test light connected to ground, check the S/C brake switch output circuit in the Speed Control servo harness connector.
NOTE: The test light must illuminate brightly.
Compare the brightness to that of a direct connection to the battery. Does the test light cycle on and off and illuminate brightly?
Yes --> Refer to the SYMPTOM: INTERMITTENT CONDITION Symptom (Diagnostic Procedure).
No --> Replace and program the ECM in accordance with the Service Information.

 

[CPesce]

Sweet. Ill do some tests. Where is the speed control servo located?

 

[cerberusiam]

Can't tell that unless you tell us what year, model, and trans in your truck. Also, where is the APPS on your truck? Under the driver side battery or left front of the engine?

 

[CPesce]

Its an 04 auto trans with the apps on the left driver side engine.