P0421 Diagnostic Trouble Code Discussion for April 2020
Warmup Catalyst Efficiency Low (Bank 1)
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| Help Request | Posted | |
| 2015 Mazda CX-5 Touring 2.5L MIL Lamp on VIN: JM3KE4DY7F P0421: Reprogrammed pcm for tsb bullitin 01-010-16. ... pulled over when all lights came, shut car off would not re-start. Towed vehicle in, replaced belt and tensioner charged battery fully and cleared all codes. Now keeps getting a code p0421 for warm up cat efficiency had it reprogrammed for tsb regardin... |
April 08, 2020 |
