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 P0405 (2018 2019 2020 2021)
DTC P0405 : EGR Valve Position Sensor Circuit Low Voltage
NOTE: Before you troubleshoot, review the general troubleshooting information .
| DTC Description | Confirmed DTC | Pending DTC |
|---|---|---|
| P0405 EGR Valve Position Sensor Circuit Low Voltage |
DTC (PGM-FI)
- Problem verification
-1. Turn the vehicle to the ON mode.
-2. Check the parameter (s) below with the HDS.
Signal Threshold Current conditions Values Unit Values Unit EGR valve position sensor (EGR VLS) Less than 0.54 V Do the current condition (s) match the threshold?
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 the EGR valve 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 .
- Open wire check (VCC2 line)
-1. Turn the vehicle to the OFF (LOCK) mode.
-2. Disconnect the following connector.
EGR valve 5P connector -3. Turn the vehicle to the ON mode.
-4. Measure the voltage between test points 1 and 2.
Test condition Vehicle ON mode EGR valve 5P connector: disconnected Test point 1 EGR valve 5P connector (female terminals) No. 2: Test point 2 EGR valve 5P connector (female terminals) No. 3: Is there about 5.0 V?
YES
The VCC2 wire is OK. Go to step 3.
NO
Repair an open in the VCC2 wire between the PCM (B29) and the EGR valve.
- Shorted wire check (EGRL line)
-1. Turn the vehicle to the OFF (LOCK) mode.
-2. Jump the SCS line with the HDS, and wait more than 1 minute.
-3. Disconnect the following connector.
PCM connector C (51P) -4. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode EGR valve 5P connector: disconnected PCM connector C (51P): disconnected Test point 1 EGR valve 5P connector (female terminals) No. 4: Test point 2 Body ground Is there continuity?
YES
Repair a short in the EGRL wire between the PCM (C23) and the EGR valve.
NO
The EGRL wire is not shorted. Go to step 4.
- Open wire check (EGRL line)
-1. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode EGR valve 5P connector: disconnected PCM connector C (51P): disconnected Test point 1 EGR valve 5P connector (female terminals) No. 4: Test point 2 PCM connector C (51P) No. 23 Is there continuity?
YES
The EGRL wire is OK. Go to step 5.
NO
Repair an open in the EGRL wire between the PCM (C23) and the EGR valve.
- PCM internal circuit check
-1. Connect terminals A and B with a jumper wire.
Terminal A EGR valve 5P connector (female terminals) No. 2: Terminal B EGR valve 5P connector (female terminals) No. 4: -2. Reconnect PCM connector C (51P).
-3. Exit the SCS mode with the HDS.
-4. Turn the vehicle to the ON mode.
-5. Check the parameter (s) below with the HDS.
Signal Threshold Current conditions Values Unit Values Unit EGR Valve Position Sensor (EGR VLS) Less than 0.54 V Do the current condition (s) match the threshold?
YES
Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM .
NO
The PCM internal circuit is OK. Replace the EGR valve .
NO RELATED
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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.