This guide addresses how to resolve the issue of the Intake Manifold 1 Air Temperature Sensor voltage being too high or showing an open circuit on JCB Tier 4 engines (K4735), fault code SPN 1132, FMI 3.
Related Contents:
Issue Description
The temperature signal from Intake Manifold 1 is detected to be above its normal operating range.
Possible Causes:
- Faulty Wiring: The wiring connected to the intake manifold temperature sensor may be damaged or compromised.
- Defective Sensor: The intake manifold temperature sensor itself may be malfunctioning.
Engine Control Module (EEM) Response
- The fault code (FC) is logged in the system.
- A warning light is illuminated on the dashboard.
- Engine performance is reduced to “degradation level 1.”
- An active error is communicated via CAN.
Step-by-Step Solution
- Save and Clear the Error Log:
- Save the existing error log and then delete it.
- Restart the ECU (Engine Control Unit) after clearing the log.
- Monitor for Recurrence:
- If the error reappears during the next operating cycle, follow these steps:
- Inspect Wiring and Connectors:
- Examine the wiring leading to the intake manifold temperature sensor for any signs of damage or wear.
- Check the sensor plug and the pin contact surfaces for signs of oxidation or poor connection.
- Test the Sensor:
- Test the intake manifold temperature sensor to confirm whether it is functioning correctly.
By following this procedure, you should be able to identify and resolve the issue.