Codes 12 &/Or 13, No Rpm Signal, No Signal For 2 Seconds: Notes
WARNING: This page is about a different car, the 1992 Geo Prizm. However, it is still accessible from the selected car via links, so may be relevant.
ECM supplies 12 volts to crank angle sensor. As the stator inside the distributor passes the crank angle sensor, 12 volts is pulled low. This signal voltage is used to fire the coil and fuel injectors. If this signal is not present for 2 seconds, Code 12 and/or 13 will set.
NOTE:
Test numbers refer to test numbers on diagnostic chart.
- Voltage is supplied by the ECM to the RPM pick-up coil.
- Determines if RPM signal is present at ECM.
- Checks for proper resistance of pick-up coil.
- Checks for proper resistance of signal rotor coil.