Case IH t80 – Engine Control Module (ECM): Pump Map, Data Valid But Below Normal Range

This code indicates a communication or internal data error regarding the fuel injection pump's mapping. The data being transmitted from the pump's control unit is recognized as a valid format, but the values fall below the normal operating threshold expected by the engine management system.

• MXM
• MXM120
• MXM130
• MXM140
• MXM155
• MXM175
• MXM190
• TM120
• TM130
• TM140
• TM155
• TM175
• TM190

1. 1

   Visually inspect the fuel injection pump for physical damage. If damaged, it must be replaced.

2. 2

   Inspect the Pump Control Unit connector (C273), the front main harness connector (C269), and the Engine Control Module connector (C316). Ensure they are tightly connected, undamaged, and have no pushed pins.

3. 3

   Check for a short to positive voltage: Disconnect C273 and C316, turn keystart ON, and measure voltage between C273 pin 8 (PC6–Y) and ground while wiggling the harness.

4. 4

   Check for an open circuit: Turn keystart OFF, measure resistance between C273 pin 8 and C316 pin 35, and between C273 pin 6 and ground. Wiggle the harness. Resistance greater than 5 Ohms indicates a fault.

5. 5

   Check for a short to ground: Test continuity between C273 pin 8 and ground while wiggling the harness.

1. 1

   Perform electrical diagnostic checks

   Perform the electrical diagnostic checks listed above to rule out a wiring issue.

2. 2

   Repair or replace harness

   If a wiring fault (short or open circuit) is found, repair the damaged section of the harness or replace the harness entirely.

3. 3

   Identify internal PCU fault

   If the harness and connectors test perfectly (resistance is approx. 5 Ohms and no shorts are present), the fault lies internally within the fuel injection pump's PCU.

4. 4

   Remove defective pump

   Remove the defective fuel injection pump assembly.

5. 5

   Install replacement pump

   Install the replacement fuel injection pump.

6. 6

   Clear codes and calibrate

   Clear the fault codes and perform any necessary transmission/engine calibrations as outlined in the MXM H-Menu calibration procedures.