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P2535




DTC P2534 or P2535

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.

* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P2534

-
Ignition 1 Switch Circuit Low Voltage

DTC P2535

-
Ignition 1 Switch Circuit High Voltage

Circuit/System Description

The transmission control module (TCM) samples the system voltage on the Ignition 1 voltage circuit every 0.1 seconds. Lower than normal voltage may be inadequate to operate the transmission control solenoids properly. Improper solenoid operation may cause erratic transmission operation, which may result in internal damage.

Conditions for Running the DTC

P2534

The Run/Crank voltage signal is valid, with ignition ON.

P2535

The TCM Run/Crank voltage signal is valid, with the ignition OFF.

Conditions for Setting the DTC

P2534

The TCM detects 5 volts or less on the ignition 1 voltage circuit at the TCM for 1.0 second or more, with the ignition turned ON.

P2535

The TCM detects greater than 6 volts on the ignition 1 voltage circuit, with the ignition turn OFF.

Action Taken When the DTC Sets

P2534

* DTC P2534 is a Type A DTC.

* The TCM turns OFF the HSD.

* The TCM turns OFF all solenoids.

* The TCM commands maximum line pressure.

* The TCM freezes transmission adaptive functions.

* The TCM commands the TCC OFF.

* The TCM allows the vehicle to operate in transmission protection mode.

* The TCM disables Tap up and Tap down functions.

P2535

* DTC P2535 is a Type A DTC.

* The ignition switch is turned OFF.

* The TCM has not power down to sleep mode.

Conditions for Clearing the DTC

DTCs P2534 and P2535 are Type A DTCs.

Diagnostic Aids

If all circuit tests are OK, ensure the transmission pass through connector and harness terminals are clean and not damaged, and the charging system is functioning correctly.

Reference Information

Schematic Reference

Automatic Transmission Controls Schematics Electrical Diagrams

Connector End View Reference

Component Connector End Views Fuel Pump and Level Sensor Assembly - Primary

Electrical Information Reference

* Circuit Testing Circuit Testing

* Connector Repairs Connector Repairs

* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections

* Wiring Repairs Wiring Repairs

Description and Operation

* Transmission General Description Transmission General Description

* Transmission Component and System Description Transmission Component and System Description

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References Control Module References for scan tool information

Circuit/System Verification

1. Engine running, accessories OFF, measure and record the battery voltage with a DMM. The battery voltage should be between 12.6-15 volts.

If not between 12.6-15 volts

Refer to Charging System Test Testing and Inspection.

If between 12.6-15 volts

2. Observe the scan tool TCM ignition voltage parameter. The parameter value should be between 12.6-15 volts.

If not between 12.6-15 volts

Refer to Circuit/System Testing below.

If between 12.6-15 volts

3. Ignition OFF.

4. Verify a test lamp does not illuminate on either test point of the fuse for the ignition voltage circuit for the Q8 control solenoid valve assembly.

If the test lamp illuminates

Refer to Circuit/System Testing below.

If the test lamp does not illuminate

5. After performing the above steps, verify that the DTC does not reset by operating the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions you observe from the Freeze Frame/Failure Records data. If the vehicle passes the Circuit/System Verification procedure, then STOP. Do not perform the Circuit/System Testing or Component Testing as this may result in an unnecessary part replacement. Refer to Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections.

Circuit/System Testing

1. Ignition OFF, and all vehicle systems OFF, disconnect the X1 16 way harness connector at the transmission.

2. Test for less than 5 ohms between terminal 5 and ground at the transmission case.

If 5 ohms or greater

1. Ignition OFF.

2. Test for less than 2 ohms in the ground circuit end to end.

If 2 ohms or greater, repair the open/high resistance in the circuit.

If less than 2 ohms, repair the open/high resistance in the ground connection

If less than 5 ohms

3. Verify a test lamp illuminates between terminal 4 and ground at the transmission case.

If the test lamp does not illuminate and the circuit fuse is good

1. Ignition OFF.

2. Test for less than 2 ohms in the B+ circuit end to end.

If 2 ohms or greater, repair the open/high resistance in the circuit.

If less than 2 ohms, verify the fuse is not open and there is voltage at the fuse.

If the test lamp does not illuminate and the circuit fuse is open

1. Ignition OFF.

2. Test for infinite resistance between the B+ circuit and ground.

If less than infinite resistance, repair the short to ground on the circuit.

If the test lamp illuminates

4. Ignition OFF.

5. Verify a test lamp does not illuminates between terminal 12 and ground at the transmission case.

If the test lamp illuminates

Test the ignition voltage circuit for a short to B+.

If the test lamp does not illuminates

6. Ignition ON.

7. Verify a test lamp illuminates between terminal 12 and ground at the transmission case.

If the test lamp does not illuminate and the circuit fuse is good

1. Ignition OFF.

2. Test for less than 2 ohms in the voltage circuit end to end.

If 2 ohms or greater, repair the open/high resistance in the circuit.

If less than 2 ohms, verify the fuse is not open and there is voltage at the fuse.

If the test lamp does not illuminate and the circuit fuse is open

1. Ignition OFF.

2. Test for infinite resistance between the voltage circuit and ground.

If less than infinite resistance, repair the short to ground on the circuit.

If the test lamp illuminates

Replace the Q8 control solenoid valve assembly.

Repair Instructions

* Perform the Reset Transmission Adapts Reset Procedure following all transmission related repairs.

* Perform the Diagnostic Repair Verification Verification Tests after completing the repair.