P151C
DTC P151C or P2516-P2518
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 Descriptors
DTC P151C
- Air Conditioning (A/C) Low Side Refrigerant Pressure Sensor Not Plausible
DTC P2516
- Air Conditioning (A/C) Low Side Refrigerant Pressure Sensor Performance
DTC P2517
- Air Conditioning (A/C) Low Side Refrigerant Pressure Sensor Circuit Low Voltage
DTC P2518
- Air Conditioning (A/C) Low Side Refrigerant Pressure Sensor Circuit High Voltage
Diagnostic Fault Information
Circuit/System Description
The Hybrid Powertrain control module (HPCM2) monitors the low side refrigerant pressure through the A/C pressure sensor. The HPCM2 supplies a 5 V reference and a low reference to the sensor. Changes in the A/C refrigerant pressure cause the sensor signal to the HPCM2 to vary. When the pressure is high, the signal voltage is high. When the pressure is low, the signal voltage is low.
Conditions for Running the DTC
P151C
* 12 V battery system voltage above 10.25 V.
* HPCM2 is awake and communicating.
* None of these DTCs may be active: P2517, P2518, P0073; P0072; P0071, P0119; P0118; P0117; P0116, P0531, P0532; P0533, P537,P538, P153B, P0606
* Outside Air Temperature raw and corrected values must have had a chance to settle out. Once this occurs these variables are assigned a status of valid. May need to have some time driving in EV mode
* Engine coolant temperature must be within 15 degrees of outside air temperature
* Outside Air Temperature between 0°C (32°F) and 25°C (77°F).
* AC compressor must have been off for an hour since the last time the AC compressor was on.
P2516
* 12 V battery system voltage above 10.25 V.
* HPCM2 is awake and communicating.
* None of these DTCs may be active: P2517, P2518, P0073; P0072; P0071, P0119; P0118; P0117; P0116, P0606
* Engine coolant temperature must be within 15 degrees of outside air temperature
* AC compressor must have been off for an hour since the last time the AC compressor was on.
* AC compressor must be turned on for one minute. (This may the require the service technician to select an HVAC mode that causes the AC compressor to run).
P2517 or P2518
* 12 V battery system voltage above 10.25 V.
* HPCM2 is awake and communicating.
Conditions for Setting the DTC
DTC P151C
The A/C low side Refrigerant Pressure reading and the A/C high side Refrigerant Pressure reading must be within 200 kPa (29 psi). and the A/C low side Refrigerant Pressure reading and the pressure derived from the A/C Refrigerant Temperature Sensor must be within 200 kPa (29 psi)
DTC P2516
The difference between the A/C low side pressure Sensor before compressor on and after compressor on changes less than 50 kPa (7 psi) over a 15 second period.
DTC P2517
The HPCM2 detects a short to ground or open at the A/C low side pressure sensor signal circuit.
DTC P2518
The HPCM2 detects a short to voltage at the A/C low side pressure sensor signal circuit.
Action Taken When the DTC Sets
These are type B DTCs.
Conditions for Clearing the DTC
These are type B DTCs.
Reference Information
Schematic Reference
HVAC Schematics Electrical Diagrams
Connector End View Reference
Component Connector End Views Hybrid/EV Battery Pack X1
Description and Operation
Automatic HVAC Description and Operation HVAC - Automatic
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
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References Programming and Relearning for scan tool information
Circuit/System Testing
1. Vehicle OFF and all vehicle systems OFF, disconnect the harness connector at the B1C A/C low side pressure sensor harness connector. It may take up to 2 minutes for all vehicle systems to power down.
2. Test for less than 10 ohm between the low reference circuit terminal 3 and ground.
• If 10 ohm or greater
1. Vehicle OFF, disconnect the harness connector at the K114B HPCM2.
2. Test for less than 2 ohm in the low reference circuit end to end.
• If 2 ohm or greater, repair the open/high resistance in the circuit.
• If less than 2 ohm, replace the K114B HPCM2.
• If less than 10 ohm
3. Vehicle in Service Mode.
4. Test for 4.8-5.2 V between the 5 V reference circuit terminal 2 and ground.
• If less than 4.8 V
1. Vehicle OFF, disconnect the harness connector at the K114B HPCM2.
2. Test for infinite resistance between the 5 V reference circuit and ground.
• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance
3. Test for less than 2 ohm in the 5 V reference circuit end to end.
• If 2 ohm or greater, repair the open/high resistance in the circuit.
• If less than 2 ohm, replace the K114B HPCM2.
• If greater than 5.2 V
1. Vehicle OFF, disconnect the harness connector at the K114B HPCM2, vehicle in Service Mode.
2. Test for less than 1 V between the 5 V reference circuit and ground.
• If 1 V or greater, repair the short to voltage on the circuit.
• If less than 1 V, replace the K114B HPCM2.
• If between 4.8-5.2 V
5. Verify the scan tool A/C Low Side Pressure Sensor parameter is less than 4.8-5.2 V.
• If 4.8-5.2 V or greater
1. Vehicle OFF, disconnect the harness connector at the K114B HPCM2, vehicle in Service Mode.
2. Test for less than 1 V between the signal circuit terminal 3 and ground.
• If 1 V or greater, repair the short to voltage on the circuit.
• If less than 1 V, replace the K114B HPCM2.
• If less than 4.8-5.2 V
6. Install a 3 A fused jumper wire between the signal circuit terminal 1 and the 5 V reference circuit terminal 2.
7. Verify the scan tool A/C Low Side Pressure Sensor parameter is greater than.02 V.
• If.02 V or less
1. Vehicle OFF, disconnect the harness connector at the K114B HPCM2.
2. Test for infinite resistance between the signal circuit terminal 1 and ground.
• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance
3. Test for less than 2 ohm in the signal circuit end to end.
• If 2 ohm or greater, repair the open/high resistance in the circuit.
• If less than 2 ohm, replace the K114B HPCM2.
• If greater than.02 V
8. Test or replace the B1C A/C refrigerant pressure sensor.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* HVAC Component Replacement Reference HVAC Component Replacement Reference
* Control Module References Programming and Relearning for control module replacement, programming and setup