Ignition ON, observe the scan tool Low Pressure Switch parameter. The parameter should read closed.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the A/C refrigerant pressure sensor.
2. Ignition OFF, test for less than 10 ohms between the low reference circuit terminal 1 and ground.
锟斤拷If greater than the specified range, test the low reference circuit for an open/high resistance.
3. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal 2 and ground.
锟斤拷If less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance.
锟斤拷If greater than the specified range, test the 5-volt reference circuit for a short to voltage.
4. Verify the scan tool Low Pressure Switch parameter is Open.
锟斤拷If not the specified value, test the signal circuit terminal 3 for a short to voltage.
5. Install a 3A fused jumper wire between the signal circuit terminal 3 and the 5-volt reference circuit terminal 2. Verify the scan tool Low
Pressure Switch parameter is Open.
锟斤拷If not the specified value, test the signal circuit for short to ground or an open/high resistance. If the circuit tests normal, replace the
HVAC control module.
6. If all circuits test normal, test or replace the A/C refrigerant pressure sensor.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
* Air Conditioning (A/C) Refrigerant Pressure Sensor Replacement (Non-HP2) (See: Heating and Air Conditioning/Refrigerant Pressure
Sensor / Switch/Service and Repair/Air Conditioning (A/C) Refrigerant Pressure Sensor Replacement)Air Conditioning (A/C) Refrigerant
Pressure Sensor Replacement (HP2) (See: Heating and Air Conditioning/Refrigerant Pressure Sensor / Switch/Service and Repair/Air
Conditioning (A/C) Refrigerant Pressure Sensor Replacement)
* Control Module References (See: Testing and Inspection/Programming and Relearning) for the HVAC control module replacement, setup,
and programming
Powertrain Management
DTC P2534
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an
overview of the diagnostic approach.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions)provides an overview of each diagnostic category.
DTC Descriptor
DTC P2534
- Ignition 1 Switch Circuit Low Voltage
Diagnostic Fault Information
Circuit/System Description
The fuel pump control module monitors the ignition voltage circuit in order to determine if the voltage is within the normal operating range.
Conditions for Running the DTC
The engine is running.
