DTC P0657
DTC P0657 : Powertrain Control Module (PCM) Power Supply Circuit Malfunction
NOTE: Before you troubleshoot, review the general troubleshooting information - Refer to: How to Troubleshoot the Fuel and Emissions Systems, or How to Troubleshoot the A/T System .
| DTC Description | Confirmed DTC | Pending DTC |
|---|---|---|
| P0657 Powertrain Control Module (PCM) Power Supply Circuit Malfunction |
DTC (PGM-FI)
- Problem verification
- 1. Turn the vehicle to the ON mode.
- 2. Clear the DTC with the HDS.
- 3. Turn the vehicle to the OFF (LOCK) mode.
- 4. Start the engine.
- 5. Check for Pending or Confirmed DTCs with the HDS.
DTC Description Confirmed DTC Pending DTC P0657 Powertrain Control Module (PCM) Power Supply Circuit Malfunction Is DTC P0657 indicated?
YES
The failure is duplicated. Go to step 2.
NO
Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at PGM-FI main relay 1 and the PCM. If the on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the on-board snapshot - Refer to: How to Troubleshoot the Fuel and Emissions Systems, or How to Troubleshoot the A/T System .
- Relay circuit board check
- 1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Remove and test the relay circuit board.
Is the relay OK?
YES
Go to step 3.
NO
- Fuse check
- 1. Check the following fuse.
Is the fuse OK?
YES
Go to step 9.
NO
Go to step 4.
- Determine possible failure area (+B MAIN RLY line, others)
- 1. Remove the blown No. A21 fuse.
- 2. Check for continuity the between following test points and body ground individually.
Test condition Vehicle OFF (LOCK) mode Relay circuit board: Disconnected Test point 1 Relay circuit board connector B (16P) No. 4 Test point 2 Body ground Is there continuity?
YES
Repair a short in the +B MAIN RLY wire between the No. A21 fuse and relay circuit board. Also replace the No. A21 fuse.
NO
Go to step 5.
- Relay check
- 1. Remove PGM-FI main relay 2.
- 2. Test PGM-FI main relay 2.
Is the relay OK?
YES
Go to step 6.
NO
Replace PGM-FI main relay 2.
- Parts internal circuit check 1
- 1. Check for continuity between test points 1 and 2 while disconnecting these parts, one at a time:
- CMP sensor 3P connector
- CKP sensor 3P connector
Test condition Vehicle OFF (LOCK) mode Relay circuit board: Disconnected PGM-FI main relay 2: Disconnected Test point 1 Relay circuit board connector B (16P) No. 8 Test point 2 Body ground Does continuity go away with the part (s) removed?
YES
Replace the part that continuity goes away when it was disconnected. Also replace the No. A21 fuse. - Refer to:
Fuse to Components Index (Without Auto Idle Stop System) (2016 2017 2018) or
Fuse to Components Index (With Auto Idle Stop System) (2016 2017 2018), or
Fuse to Components Index (Without Auto Idle Stop System) (2019 2020 2021) or
Fuse to Components Index (With Auto Idle Stop System) (2019 2020 2021)
NO
Go to step 7.
- Parts internal circuit check 2
- 1. Jump the SCS line with the HDS, and wait more than 1 minute.
- 2. Check for continuity between test points 1 and 2 while disconnecting following part:
PCM connector A (50P) Test condition Vehicle OFF (LOCK) mode Relay circuit board: Disconnected PGM-FI main relay 2: Disconnected Test point 1 Relay circuit board connector B (16P) No. 10 Test point 2 Body ground Does continuity go away with the part removed?
YES
Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM - Refer to: PCM Removal and Installation (6-Speed A/T, 16-18 9-Speed A/T), or PCM Removal and Installation (19-21 9-Speed A/T) , then recheck. If DTC P0657 goes away and the PCM was substituted, replace the original PCM - Refer to: PCM Removal and Installation (6-Speed A/T, 16-18 9-Speed A/T), or PCM Removal and Installation (19-21 9-Speed A/T) .
Also replace the No. A21 fuse. - Refer to:
Fuse to Components Index (Without Auto Idle Stop System) (2016 2017 2018) or
Fuse to Components Index (With Auto Idle Stop System) (2016 2017 2018), or
Fuse to Components Index (Without Auto Idle Stop System) (2019 2020 2021) or
Fuse to Components Index (With Auto Idle Stop System) (2019 2020 2021)
NO
Go to step 8.
- Shorted wire check (IGP line)
- 1. Connect terminals A, B and C with a jumper wire.
Terminal A Relay circuit board connector B (16P) No. 8 Terminal B Relay circuit board connector B (16P) No. 9 Terminal C Relay circuit board connector B (16P) No. 10 - 2. Disconnect the following parts and connectors.
PCM connector A (50P) CMP sensor 3P connector CKP sensor 3P connector - 3. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode Relay circuit board: Disconnected Relay circuit board connector B (16P) No. 8, No. 9 and No. 10: Jumped PCM connector A (50P): disconnected PGM-FI main relay 2: Disconnected CMP sensor 3P connector: disconnected CKP sensor 3P connector: disconnected Test point 1 PCM connector A (50P) No. 4 - Refer to:
PCM Connector for Inputs and Outputs (16-18, 9-Speed A/T), or
PCM Connector for Inputs and Outputs (9-Speed A/T) (2019 2020 2021), or
PCM Connector for Inputs and Outputs (16-20 6-Speed A/T)Test point 2 Body ground Is there continuity?
YES
Repair a short in the IGP line between the PCM (A4), the relay circuit board, the CMP sensor, the CKP sensor, PGM-FI main relay 2 and the No. A11 fuse. - Refer to:
Fuse to Components Index (Without Auto Idle Stop System) (2016 2017 2018) or
Fuse to Components Index (With Auto Idle Stop System) (2016 2017 2018), or
Fuse to Components Index (Without Auto Idle Stop System) (2019 2020 2021) or
Fuse to Components Index (With Auto Idle Stop System) (2019 2020 2021)
Also replace the No. A21 fuse. - Refer to:
Fuse to Components Index (Without Auto Idle Stop System) (2016 2017 2018) or
Fuse to Components Index (With Auto Idle Stop System) (2016 2017 2018), or
Fuse to Components Index (Without Auto Idle Stop System) (2019 2020 2021) or
Fuse to Components Index (With Auto Idle Stop System) (2019 2020 2021)
NO
Replace relay circuit board. Also replace the No. A21 fuse.
- Determine possible failure area (PGM-FI main relay 1 control circuit, others)
- 1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Remove the No. A23 fuse.
- 3. Reinstall the relay circuit board.
- 4. Jump the SCS line with the HDS, and wait more than 1 minute.
- 5. Disconnect the following connector.
PCM connector A (50P) - 6. Measure the voltage between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode PCM connector A (50P): disconnected Test point 1 PCM connector A (50P) No. 22 - Refer to:
PCM Connector for Inputs and Outputs (16-18, 9-Speed A/T), or
PCM Connector for Inputs and Outputs (9-Speed A/T) (2019 2020 2021), or
PCM Connector for Inputs and Outputs (16-20 6-Speed A/T)Test point 2 Body ground Is there battery voltage?
YES
Go to step 12.
NO
Go to step 10.
- Determine possible failure area (+B MAIN RLY line, others)
- 1. Disconnect the following connector.
Relay circuit board connector B (16P) - 2. Measure the voltage between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode PCM connector A (50P): disconnected Relay circuit board connector B (16P): disconnected Test point 1 Relay circuit board connector B (16P) No. 4 Test point 2 Body ground Is there battery voltage?
YES
Go to step 11.
NO
Repair an open in the +B MAIN RLY wire between the No. A21 fuse and the relay circuit board. - Refer to: Fuse to Components Index (Without Auto Idle Stop System) (2016 2017 2018) or Fuse to Components Index (With Auto Idle Stop System) (2019 2020 2021), or Fuse to Components Index (Without Auto Idle Stop System) (2019 2020 2021), or Fuse to Components Index (With Auto Idle Stop System) (2016 2017 2018)
- Open wire check (M RLY line)
- 1. Disconnect the following connector.
Relay circuit board connector A (10P) - 2. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode PCM connector A (50P): disconnected Relay circuit board: disconnected Test point 1 Relay circuit board connector A (10P) No. 9 Test point 2 PCM connector A (50P) No. 22 - Refer to:
PCM Connector for Inputs and Outputs (16-18, 9-Speed A/T), or
PCM Connector for Inputs and Outputs (9-Speed A/T) (2019 2020 2021), or
PCM Connector for Inputs and Outputs (16-20 6-Speed A/T)Is there continuity?
YES
Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM - Refer to: PCM Removal and Installation (19-21 9-Speed A/T), or PCM Removal and Installation (6-Speed A/T, 16-18 9-Speed A/T) , then recheck. If DTC P0657 goes away and the PCM was substituted, replace the original PCM - Refer to: PCM Removal and Installation (19-21 9-Speed A/T), or PCM Removal and Installation (6-Speed A/T, 16-18 9-Speed A/T) .
NO
Repair an open in the M RLY wire between the PCM (A22) and the relay circuit board.
- Open wire check (IGP line)
- 1. Disconnect the following connector.
Relay circuit board connector B (16P) - 2. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode PCM connector A (50P): disconnected Relay circuit board connector B (16P): disconnected Test point 1 Relay circuit board connector B (16P) No. 10 Test point 2 PCM connector A (50P) No. 4 - Refer to:
PCM Connector for Inputs and Outputs (16-18, 9-Speed A/T), or
PCM Connector for Inputs and Outputs (9-Speed A/T) (2019 2020 2021), or
PCM Connector for Inputs and Outputs (16-20 6-Speed A/T)Is there continuity?
YES
Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM - Refer to: PCM Removal and Installation (6-Speed A/T, 16-18 9-Speed A/T), or PCM Removal and Installation (19-21 9-Speed A/T) , then recheck. If DTC P0657 goes away and the PCM was substituted, replace the original PCM - Refer to: PCM Removal and Installation (6-Speed A/T, 16-18 9-Speed A/T), or PCM Removal and Installation (19-21 9-Speed A/T) .
NO
Repair an open in the IGP wire between the PCM (A4) and the relay circuit board.