DTC P1658 (19-21 9-Speed A/T)
DTC P1658 : Electronic Throttle Control System (ETCS) Control Relay ON Malfunction
NOTE: Before you troubleshoot, review the general troubleshooting information - Refer to: How to Troubleshoot the Fuel and Emissions Systems .
| DTC Description | Confirmed DTC | Pending DTC |
|---|---|---|
| P1658 Electronic Throttle Control System (ETCS) Control Relay ON Malfunction |
DTC (PGM-FI)
- Problem verification
- 1. Turn the vehicle to the ON mode.
- 2. Select the ETCS TEST in the INSPECTION MENU with the HDS.
ETCS TEST
Is the result OK?
YES
Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the relay circuit board (ETCS control relay circuit) 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 .
NO
The failure is duplicated. Go to step 2.
- 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
- Shorted wire check (DBW RLY line)
- 1. Jump the SCS line with the HDS, and wait more than 1 minute.
- 2. Disconnect the following connector.
PCM connector A (50P) - 3. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode Relay circuit board: disconnected PCM connector A (50P): disconnected Test point 1 PCM connector A (50P) No. 41 - Refer to:
PCM Connector for Inputs and Outputs (9-Speed A/T) (2019 2020 2021)Test point 2 Body ground Is there continuity?
YES
Repair a short in the DBW RLY wire between the PCM (A41) and the relay circuit board.
NO
The DBW RLY wire is OK. Go to step 4.
- Shorted wire check (IG1 (DBW) line to power)
- 1. Turn the vehicle to the ON mode.
- 2. Measure the voltage between test points 1 and 2.
Test condition Vehicle ON mode Relay circuit board: disconnected PCM connector A (50P): disconnected Test point 1 PCM connector A (50P) No. 2 - Refer to:
PCM Connector for Inputs and Outputs (9-Speed A/T) (2019 2020 2021)Test point 2 Body ground Is there battery voltage?
YES
Repair a short to power in the IG1 (DBW) wire between the PCM (A2) and the relay circuit board.
NO
The IG1 (DBW) wire is OK. 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) , then recheck. If DTC P1658 goes away and the PCM was substituted, replace the original PCM - Refer to: PCM Removal and Installation (19-21 9-Speed A/T) .