Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptor
DTC P2534: Ignition 1 Switch Circuit Low VoltageDiagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Ignition 1 Voltage | P2534 | P2534 | -- | P0562, P0563 |
Typical Scan Tool Data
Circuit | Normal | Short to Ground | Open/High Resistance | Short to Voltage |
|---|---|---|---|---|
Operating Conditions: Engine running in Park, normal operating temperature Parameter Normal Range: 12.0-14.5 volts | ||||
Ignition Voltage | 12.0-14.5 V | 0 V | 0 V | 12.0-14.5 V |
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
The engine is running.
Conditions for Setting the DTC
The TCM detects an open or short to ground on the Ignition 1 voltage circuit.
Action Taken When the DTC Sets
| • | DTC P2534 is a Type A DTC. |
| • | The TCM commands maximum line pressure. |
| • | The TCM commands an immediate landing to 2nd gear. |
| • | The TCM freezes transmission adaptive functions. |
Conditions for Clearing the DTC
DTC P2534 is a Type A DTC.
Reference Information
Schematic Reference
Automatic Transmission Controls Schematics
Connector End View Reference
Description and Operation
Charging System Description and Operation
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information
Special Tools
J 44152 Jumper Harness (20 pins)
Circuit/System Verification
- Engine running, accessories OFF, measure and record the battery voltage at the battery terminals. The voltage should be between 12.6 and 14.5 volts.
- Observe the scan tool TCM Ignition voltage parameter. The reading should be between 12.6 and 14.5 volts.
- Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
| ⇒ | If not within the specified range, refer to Charging System Test . |
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the TCM.
- Test for less than 10 ohm of resistance between the ground circuit terminal 49 and ground.
- Verify that a test lamp illuminates between the B+ circuit terminal 32 and ground.
- Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 31 and ground.
- If all circuits test normal, replace the TCM.
| ⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
| ⇒ | If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. |
| ⇒ | If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the repair.
Control Module References for TCM replacement, setup, and programming.
