P045D
EGR B Control Circuit High
EGR / emissions
Generic OBD-II
Medium
What it means
P045D means the ECM has detected a higher-than-expected voltage on the "B" EGR valve control circuit — usually a wiring short to voltage, a bad connector, or a faulty EGR valve/solenoid. The EGR system recirculates exhaust to lower emissions. This is an electrical control-circuit fault, so it won't stop the car from starting, but it should be fixed to keep the engine running cleanly.
Medium
Can I keep driving? Yes — the engine starts and runs, but you may notice pinging under load and it will likely fail an emissions test until repaired.
Common symptoms
What you'll notice
- Check-engine light on
- Occasional pinging or knock under acceleration or load
- Slightly rough running or hesitation at times
- Failed emissions test
Common causes
Most likely first
- Wiring shorted to voltage in the EGR 'B' control circuitLikely
- Faulty EGR valve or control solenoidCommon
- Corroded or poor electrical connector at the valve/solenoidCommon
- Carbon buildup causing the valve to stick and mis-reportLess often
- ECM fault (rare)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and note the conditions when the code set.
- Inspect the EGR 'B' control wiring and connector for shorts to voltage, chafing, or corrosion.
- Test the EGR valve/solenoid resistance against spec; replace if out of range.
- Clean the EGR valve and passages if carbon buildup is present.
- Repair wiring or replace the valve/solenoid, then clear and re-test.
FAQ
Quick answers
Is it safe to drive with P045D?+
Yes for the short term — this is an EGR control-circuit fault, not a no-start. Repair it to avoid pinging and a failed smog test.
Can I just clear P045D?+
It will come back until the wiring, connector, or valve fault is fixed. 'Circuit High' points to an electrical problem, so start there.
Related codes
Often seen with P045D
Read & clear P045D yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX