P0421 Code - Cat Or Sensor ?
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Joined: Feb 2005
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From: Beaumont, Alberta, Canada
Re: P0421 Code - Cat Or Sensor ?
DTC
Description of malfunction
Corrective action
SAE VAG
P0421 16805 Warm Up Catalyst, Bank 1
Efficiency Below Threshold 2)
- Generate readiness code Page 01-110 , if same DTC is displayed again, replace warm up catalytic converter bank 1
Repair Manual; 2.7 Liter V6 5V BiTurbo Engine Mechanical, Engine Code(s): APB, BEL; Repair Group 26
2) With this malfunction the exhaust Malfunction Indicator Light (MIL) is only switched on by the ECM, if the malfunction is recognized after the engine has been restarted. Significance of MIL Page 01-2 .
Important note:
The warm up catalytic converters are located between the two oxygen sensors of the relevant cylinder bank. The warm up catalytic converters (marginally smaller than main catalytic converter) are located closer to the engine, not to be confused with the main catalysts immediately visible once the vehicle is lifted.
Description of malfunction
Corrective action
SAE VAG
P0421 16805 Warm Up Catalyst, Bank 1
Efficiency Below Threshold 2)
- Generate readiness code Page 01-110 , if same DTC is displayed again, replace warm up catalytic converter bank 1
Repair Manual; 2.7 Liter V6 5V BiTurbo Engine Mechanical, Engine Code(s): APB, BEL; Repair Group 26
2) With this malfunction the exhaust Malfunction Indicator Light (MIL) is only switched on by the ECM, if the malfunction is recognized after the engine has been restarted. Significance of MIL Page 01-2 .
Important note:
The warm up catalytic converters are located between the two oxygen sensors of the relevant cylinder bank. The warm up catalytic converters (marginally smaller than main catalytic converter) are located closer to the engine, not to be confused with the main catalysts immediately visible once the vehicle is lifted.
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kgrig
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Feb 17, 2008 08:04 PM
