Service engine light came on a few weeks ago. Had a diagnostic ran & it came up P1478 "Particulate Matter Sensor Temperature Circuit High Voltage". Did my research & it seems one of two problems may have occurred.
Wire harness has burned through by contacting the exhaust pipe.
The sensor has went bad.
Either way, I figured the sensor would need to be replaced. With my truck being a 2021, parts haven't made it to third party places like Auto Zone & O'Reilly's. Called the dealership & they wanted $184 for the AC Delco part. Went to the AC Delco store on Amazon & bought it for $83 & free Prime shipping. The part arrived & I am having my mechanic install it on 1/24/25. I will report back if the problem is fixed.
On a side note, it does not appear this issue has caused any problems with MPG or performance.
Update from Feb 7, 2025: I purchased the new sensor from the AC Delco store on Amazon. I had my local mechanic install the new sensor & clear the code. It's been about two weeks now & the new sensor seems to have fixed the issue. My remote start is working again after the part replacement & codes cleared
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Service engine light came on a few weeks ago. Had a diagnostic ran & it came up P1478 "Particulate Matter Sensor Temperature Circuit High Voltage". Did my research & it seems one of two problems may have occurred.
Either way, I figured the sensor would need to be replaced. With my truck being a 2021, parts haven't made it to third party places like Auto Zone & O'Reilly's. Called the dealership & they wanted $184 for the AC Delco part. Went to the AC Delco store on Amazon & bought it for $83 & free Prime shipping. The part arrived & I am having my mechanic install it on 1/24/25. I will report back if the problem is fixed.
On a side note, it does not appear this issue has caused any problems with MPG or performance.
Update from Feb 7, 2025: I purchased the new sensor from the AC Delco store on Amazon. I had my local mechanic install the new sensor & clear the code. It's been about two weeks now & the new sensor seems to have fixed the issue. My remote start is working again after the part replacement & codes cleared
- Trace D., Scottsburg, IN, US