Case IH t7C – PCU: EEPROM In PCU, Data Valid But Below Normal Range

This code indicates that the non-volatile memory (EEPROM) inside the Pump Control Unit (PCU) contains data that is technically valid but falls below the expected normal operating parameters. This typically points to memory corruption, a software glitch, or an internal hardware failure within the injection pump's control module.

• MXM
• MXM 120
• MXM 130
• MXM 140
• MXM 155
• MXM 175
• MXM 190
• TM120
• TM130
• TM140
• TM155
• TM175
• TM190

1. 1

   Check for under-voltage (supply voltage low) or over-voltage (supply voltage high) conditions, as voltage spikes or drops can cause EEPROM memory corruption

2. 2

   Check for accompanying CAN BUS message faults (e.g., Error Codes 11, 13, or 17) which might indicate a communication breakdown between the tractor's main controllers and the PCU

3. 3

   Inspect the wiring harness and connectors at the injection pump with the key switch OFF for corrosion, pushed pins, or moisture, and measure circuit resistance to ensure no shorts to ground or open circuits

4. 4

   Verify if the non-volatile memory has been recently reset (H8 code) in the controller, which can sometimes trigger EEPROM range errors

1. 1

   Clear and Retest

   Attempt to clear the fault codes and perform a battery disconnect reset. If the t7C code immediately returns, the EEPROM data is permanently corrupted or the module has failed.

2. 2

   Component Replacement

   Because the EEPROM is an internal component of the Pump Control Unit, the PCU cannot usually be repaired in the field. You must remove the fuel injection pump assembly and either send it to a specialized diesel shop for a PCU rebuild/reprogramming, or replace the entire injection pump assembly.

3. 3

   Calibration

   If the microprocessor/PCU or the entire injection pump is replaced, a mandatory Transmission/EDC (Electronic Diesel Control) Calibration must be performed using the tractor's H-Menu (mode HA).

4. 4

   Initialization

   Start the engine, bring the engine speed to 1200 ERPM, and follow the specific MXM/TM calibration setup procedures to sync the new pump map data with the tractor's main modules.