Diagnostic Instructions
DTC Descriptor
DTC P2534: Ignition 1 Switch Circuit Low Voltage
Diagnostic Fault Information
Circuit
| Short to Ground
| Open/High Resistance
| Short to Voltage
| Signal Performance
|
Ignition 1 voltage
| P2534 open fuse
| P2534
| --
| P0562, P0563
|
Circuit/System Description
The transmission control module (TCM) continuously monitors the system voltage on the Ignition 1 voltage circuit. 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 speed is greater than 500 RPM for 5 seconds. |
| • | Ignition voltage is between 9.0 volts and 19.0 volts. |
Conditions for Setting the DTC
The TCM detects 2 volts or less on the ignition 1 voltage circuit at the TCM for 6 seconds or more.
Action Taken When the DTC Sets
| • | DTC P2534 is a Type A DTC. |
| • | The TCM turns OFF all high side drivers. |
| • | 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 inhibits TU TD/MUMD operation. |
Conditions for Clearing the DTC
DTC P2534 is a Type A DTC.
Diagnostic Aids
| • | Observe the driver information center (DIC) messaging that would indicate the electrical system requires service. |
| • | Inspect for the following conditions: |
| - | Loose or damaged terminals at the generator |
| - | Loose or worn generator drive belt |
Reference Information
Schematic Reference
Automatic Transmission Controls Schematics
Connector End View Reference
Component Connector End Views
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
DT-48616-10 Adapter Harness
For equivalent regional tools, refer to
Special Tools.
Circuit/System Verification
- Engine ON, accessories OFF, measure and record the battery voltage at the battery terminals. The voltage should be between 12.6-15.0 volts.
- Observe the scan tool TCM Ignition Voltage parameter. The reading should be between 12.6-15.0 volts.
- Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
Circuit/System Testing
- Ignition OFF, disconnect the 14-way harness connector at the transmission.
- Connect the
DT-48616-10 harness
to the 14-way transmission harness connector.
- Test for less than 10 ohms between the ground circuit terminal 2 and ground.
| ⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
- Ignition ON, verify that a test lamp illuminates between the ignition circuit terminals listed below and ground.
| ⇒ | If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance. |
- If all circuits test normal, replace the control solenoid (w/body and TCM) valve assembly.
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Refer to
Control Module References for control solenoid (w/body and TCM) valve assembly replacement, setup, and programming. |
