Signal Too Low - Intermittent Fault

ECM-1400 MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR
SIGNAL TOO LOW - INTERMITTENT FAULT

Checking cables and connectors



Check reference voltage cable between control module connector # A58 (# A60) and manifold absolute pressure (MAP) sensor connector terminal 3 for an intermittent open-circuit according to [1][2]Checking Wiring and Terminals. Intermittent Faults or an intermittent short-circuit to ground according to [1][2]Checking Wiring and Terminals. Intermittent Faults

Hint: With the ignition on and manifold absolute pressure (MAP) sensor connector disconnected the voltage between terminal 3 and ground terminal should be approximately 5V.

Check signal cable between control module connector # A23 (# A23) and manifold absolute pressure (MAP) sensor connector terminal 1 for an intermittent short-circuit to ground according to [1][2]Checking Wiring and Terminals. Intermittent Faults

Hint: With the ignition on and manifold absolute pressure (MAP) sensor connector disconnected the voltage between terminal 1 and ground terminal should be approximately 5V.

Other information:
- To connect the breakout box, Connecting the Breakout Box (ECM)
- To access/replace the control module, Engine Control Module (ECM), Replacing
- For information about signals, Pinout Values and Diagnostic Parameters
- To localize the manifold absolute pressure (MAP) sensor, Locations


Fault-tracing information
If the fault is intermittent, do not verify fault-tracing if the fault does not recur.