Signal Sporadic. Intermittent Fault

SIGNAL SPORADIC. INTERMITTENT FAULT





Checking Cables and Terminals

- Check atmospheric pressure sensor and engine control module (ECM) connectors for loose connections, contact resistance and oxidation.
- Check cable between atmospheric pressure sensor terminal 1 and engine control module (ECM) #B29 for an intermittent open-circuit, intermittent short-circuit to ground and an intermittent short-circuit to supply voltage.
- Check the cable between atmospheric pressure sensor terminal 3 and engine control module (ECM) #B22 for an intermittent open-circuit, intermittent short-circuit to ground and an intermittent short-circuit to supply voltage.
- Check cable between atmospheric pressure sensor terminal 2 and engine control module (ECM) #B28 for an intermittent open-circuit.
- The atmospheric pressure sensor power cable is connected inside the engine control module (ECM) to the air conditioning (A/C) pressure sensor, fuel tank pressure sensor and accelerometer power cables. If anything happens to any of these cables all four will be affected.

- Check cables between:

- Air conditioning (A/C) pressure sensor terminal 3 and engine control module (ECM) #B29
- Tank pressure sensor terminal 1 and engine control module (ECM) #B15.
- Accelerometer terminal 1 and engine control module (ECM) #Bl for intermittent the short-circuit to supply voltage and an intermittent short circuit to ground.

- Then proceed to test step below.

Fault-Tracing Information

- For intermittent faults fault-tracing is not followed by a verification because the fault is not present at this moment.
- Do you want to repeat fault-tracing?

Yes:
- Return to Checking Cables and Treminals section above.

No:
- Operation done.