Engine Shutoff Solenoid Malfunction
The PCM has detected a malfunction in the engine shutoff solenoid circuit. This is part of the system which is charged with shutting the engine down in the event of a lack of crankshaft position signal or missing primary ignition voltage signal.
Code Set Parameters
If the PCM fails to detect the proper amount of voltage and/or resistance in the engine shutoff solenoid circuit, a code could be stored and a service engine soon lamp illuminated. Some applications may require multiple failure cycles I order for a malfunction indicator lamp to be illuminated; others will illuminate on the first failure.
Symptoms may range from nothing at all to a no start condition. Typically, a service engine soon lamp will be illuminated and a trouble code will be stored.
The most common cause of this code is a defective engine shutdown relay. Other causes may include shorted, open, corroded, or disconnected electrical wiring and/or connectors, a faulty crankshaft position sensor or circuitry, or a bad PCM.
Technicians report that components commonly replaced in error include: fuel pumps, crankshaft position sensors, camshaft position sensors, and PCMs. PCM failure is rare.
- Some vehicles use engine shutoff solenoid/relay in order to deactivate the fuel pump and prevent engine damage I the absence of a primary ignition signal or a crankshaft position sensor signal
- Other automakers use no such system and allow the engine to stall on its own
- This type of code will be stored in vehicles that utilize the first type of system.
A scanner or code reader, a digital volt ohmmeter, and access to a manufacturer’s wiring schematic will be necessary to successfully diagnose this code
Begin your diagnosis with a visual inspection of all wiring and connectors
- Repair or replace damaged, disconnected, shorted, or corroded wiring, connectors, and components as necessary
- Always retest the system after repairs are completed to ensure success.
If all system wiring, connectors, and components (Including fuses) appear to be in normal working order, connect the scanner (or code reader) to the diagnostic connector and record all stored codes and freeze frame data
- This information can be extremely helpful in diagnosing intermittent conditions that may have contributed to this code being stored
- After the codes are cleared, operate the vehicle to see if the code returns
- If the code fails to immediately return, you may have an intermittent condition
- Intermittent conditions can prove to be quite a challenge to diagnose and in extreme cases may have to be allowed to worsen before a correct diagnosis can be made.
Carry on with a visual inspection of the battery cables and battery cable ends
- Clean or replace cables and ends as required
- Make sure that the battery is fully charged and then perform a battery load and starting/charging system test
- Compare your findings with manufacturer’s recommendations and replace faulty components as needed
If the battery and starting/charging system are normal, then test system fuses and fusible links
- Replace faulty components as needed and retest the system
- Without a constant supply of battery voltage to the PCM, your vehicle could continue to store trouble codes, stall at idle or under acceleration, or exhibit a no start condition.
Proceed by connecting the scanner to the vehicle and recording all stored trouble codes and freeze frame data
- This information may be crucial in helping you to diagnose this code
- Freeze frame data can be particularly helpful when diagnosing an intermittent code (or codes)
- Clear the trouble codes and operate the vehicle to see if they return
- If the code fails to reset, you have an intermittent malfunction
- These can be virtually impossible to diagnose correctly
- You may be forced to wait and allow the problem to worsen
- If the code resets, or if you are dealing with a no start condition, begin by unplugging the PCM relay connector
- Test for voltage and ground signals on the appropriate circuits and compare your findings with the wiring schematic or manufacturer’s specifications
- Probe any circuits that do not coincide with the manufacturer’s specification with the digital volt/ohmmeter (be sure to disconnect the PCM and other related control module connectors before testing individual circuits for continuity and resistance)
- Repair open, disconnected, or shorted circuits as required and retest the system.
If all of the circuits in the solenoid/relay connector are in line with manufacturer’s specs and the relay fails to provide an output signal to the PCM, suspect a faulty solenoid/relay
If all system circuits check out, and the PCM relay is providing all necessary power and ground circuits, suspect a faulty PCM
- PCM replacement will require reprograming of one or more control modules