Operation CHARM: Car repair manuals for everyone.

Code Set Parameters

11 - OXYGEN SENSOR: Minimum three minutes since start up, coolant temperature above 176°F, RPM between 2300 and 4000 RPM, 02 voltage stays less than 0.6v or stays more than 0.6v for 20 seconds.

12 - AIR FLOW SENSOR: RPM more than 500 and air flow sensor output is less than 10 hertz for four seconds.

13 - INTAKE AIR TEMPERATURE SENSOR: Engine running for 60 seconds, voltage above 4.5v or below 0.27v for 4 seconds.

14 - THROTTLE POSITION SENSOR: Engine running for 60 seconds, TPS output voltage is less than 0.2v, or more than 2v, when THROTTLE POSITION SWITCH IS CLOSED. Must occur for more than 4 seconds.

15 - ISC MOTOR POSITION SENSOR: Engine running for 60 seconds, MPS voltage above 4.8v or below 0.2 v, for more than 4 seconds. ISC motor will be driven closed.

21 - COOLANT TEMPERATURE SENSOR: Engine running for 60 seconds, output voltage is less than .11v or more than 4.6v for 4 seconds.

22 - CRANK ANGLE SENSOR: No signal change to the ECU for 4 seconds. Monitored during engine cranking.

23 - TOP DEAD CENTER SENSOR: No signal change for 4 seconds with engine running for more than 1 minute and more than 500 rpm.

24** - VEHICLE SPEED SENSOR: Engine running for more than 60 seconds, RPM above 3000 and heavy engine load. Idle switch must be off. No speed sensor change for 4 seconds.

25 - BAROMETRIC PRESSURE SENSOR: Engine running for more than 60 seconds, output voltage above 4.5v or below 0.2v, for more than 4 seconds.

41 - INJECTOR: Below 1000 RPM, TPS output less than 0.7v, "injector output circuit is less than 2v, when injector is not operated".

42 - FUEL PUMP: No voltage to pin 109 of the ECU from the control relay. (Relay is closed by ECU above 50 engine RPM.)

43 - California Only: EGR TEMP SENSOR: Engine running for more than 6 minutes, coolant temp above 176°F, engine RPM above 2300, intake air temp below 131°F, EGR temp sensor indicates less than 535°F for 4 sec.

NOTE: It is important to be aware that the ECU will recognize a circuit failure and initiate a compensation sequence within 10 to 20 milliseconds on most circuits. Fault code set, however, is usually delayed for another 4 seconds. This can make intermittent driveability complaints with no fault codes very difficult to pinpoint.

** WILL NOT TURN ON CHECK ENGINE LIGHT