Case IH t17 – PCU: PCU power supply, data valid but above normal range.

The voltage or power supply feeding the PCU is registering as higher than the acceptable operating threshold, though the data itself is still readable.

• MXM
• MXM 120
• MXM 130
• MXM 140
• MXM 155
• MXM 175
• MXM 190

1. 1

   Verify the power supply voltage going to the PCU.

2. 2

   Check the tractor's charging system (alternator/voltage regulator) to ensure it is not overcharging.

3. 3

   Inspect the wiring harness for a short to a high-voltage source.

4. 4

   Perform a controller swap test by temporarily connecting a known-good EEM2 controller from another tractor to isolate whether the issue is the PCU or the engine controller (Note: this will trigger a pump serial number mismatch code).

1. 1

   Resolve Power Supply Issues

   If the diagnostic checks reveal an overcharging alternator or a wiring short to a high source, repair the wiring harness or replace the voltage regulator/alternator as needed.

2. 2

   Replace the EEM2 Controller

   If the controller swap test causes the PCU power supply fault to disappear, the original EEM2 controller is damaged. Replace the controller and use the EEM2 Service Tool to couple the current injection pump's serial number to the new EEM2 controller.

3. 3

   Replace the PCU

   If the fault does not disappear when testing with a good EEM2 controller, the Bosch VP PCU itself is internally damaged. The injection pump/PCU assembly will need to be removed and serviced or replaced.