Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
DTC P1658
DTC P1658 : ETCS Control Relay ON Malfunction
NOTE: Before you troubleshoot, review the general troubleshooting information .
| DTC Description | Confirmed DTC | Pending DTC | Freeze Frame |
|---|---|---|---|
| P1658 ETCS Control Relay ON Malfunction |
DTC (PGM-FI)
- Problem verification
-1. Turn the vehicle to the ON mode.
-2. Do the ETCS TEST with the HDS.
ETCS (TAC) TEST
Is the RELAY circuit OK?
YES
Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the ETCS control relay and the PCM. If the freeze data/on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the freeze data/on-board snapshot .
NO
The failure is duplicated. Go to step 2.
- ETCS control relay test
-1. Turn the vehicle to the OFF (LOCK) mode.
-2. Remove the ETCS control relay (A) from the under-hood fuse/relay box.
-3. Test the ETCS control relay .
Is the ETCS control relay OK?
YES
The ETCS control relay is OK. Go to step 3.
NO
Replace the ETCS control relay.
- Shorted wire check (DBW RLY CL- line)
-1. Turn the vehicle to the OFF (LOCK) mode.
-2. Jump the SCS line with the HDS.
-3. Disconnect the following connector.
PCM connector A (51P) -4. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode ETCS control relay: disconnected PCM connector A (51P): disconnected Test point 1 PCM connector A (51P) No. 50 Test point 2 Body ground Is there continuity?
YES
Repair a short in the DBW RLY CL- wire between the PCM (A50) and the throttle body.
NO
The DBW RLY CL- wire is OK. Go to step 4.
- Shorted wire check (DBW RLY OUT/VBDBW line to power)
-1. Disconnect the following connector.
PCM connector C (51P) -2. Turn the vehicle to the ON mode.
-3. Measure the voltage between test points 1 and 2.
Test condition Vehicle ON mode ETCS control relay: disconnected PCM connector A (51P): disconnected PCM connector C (51P): disconnected Test point 1 PCM connector C (51P) No. 1 Test point 2 Body ground Is there battery voltage?
YES
Repair a short to power in the DBW RLY OUT/VBDBW wire between the PCM (C1) and the ETCS control relay.
NO
The DBW RLY OUT/VBDBW wire is OK. Update the PCM if it does not have the latest software, or substitute a known-good PCM , then recheck. If DTC P1658 goes away and the PCM was updated, troubleshooting is complete. If DTC P1658 goes away and the PCM was substituted, replace the original PCM .
NO RELATED
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.