P0421 Diagnostic Trouble Code Discussion for January 2016
Warmup Catalyst Efficiency Low (Bank 1)
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| Help Request | Posted | |
| 2007 Mazda CX-7 Touring 2.3L MIL Lamp on VIN: JM3ER29347 P0421: Warmup Catalyst Efficiency Below Normal. The customer brought this in saying that it needed a catalytic converter. As I was looking the data on my scantool I noticed the heater on the downstream o2 sensor (B1S2)does not or isn't signaled to turn on until after the engine had reached normal operating ... |
January 11, 2016 | |
| 2007 Mazda CX-7 Touring 2.3L MIL Lamp on VIN: JM3ER29347 P0421: Warmup Catalyst Efficiency Below Normal. The customer brought this in saying that it needed a catalytic converter. As I was looking the data on my scantool I noticed the heater on the downstream o2 sensor (B1S2)does not or isn't signaled to turn on until after the engine had reached normal operating ... |
January 29, 2016 |
