Case IH 3283 (F-3510-12) - ECU – Engine ECU (ECM): ECM 5 volt sensor supply 2 out of range failure

The Engine Control Module (ECM) has detected that the voltage on the #2 regulated 5-volt sensor supply circuit is exceeding the normal operating range (shorted to a high source, such as battery voltage).

• VESTRUM CVX
• Case IH Skid Steer Loaders (SSL)
• Case IH Compact Track Loaders (CTL)
• Case IH Farmall tractors

1. 1

   Identify the #2 5-volt supply circuit routing through the 94-pin Vehicle Side Connector (K) and 60-pin Engine Connector (A), specifically pins K12, K13, K14, K15, and K16.

2. 2

   Check for sensor shorts by disconnecting the sensors on the #2 5-volt supply one at a time while monitoring the circuit voltage or active fault codes to see if the voltage drops back to normal.

3. 3

   Inspect the engine wiring harness for chafing, rubbing, or pinched wires that could cause the 5V supply wire to short against a 12V power source.

4. 4

   Disconnect the Engine ECU and inspect the pins for corrosion, moisture, or bent terminals.

1. 1

   Turn key OFF

   Turn the key switch OFF before disconnecting any modules or sensors.

2. 2

   Isolate the short

   Disconnect the engine wiring harness from the Engine ECU. Measure the voltage on the #2 5-volt supply pins (K12-K16) with the key ON to determine if the short is in the harness or internal to the ECU.

3. 3

   Repair harness or replace sensor

   If disconnecting a specific sensor clears the short, replace that sensor. If the harness is shorted to battery voltage, locate the chafed section of the harness and repair the wiring, or replace the engine wiring harness entirely.

4. 4

   Replace Engine ECU

   If the harness and all sensors test good, but the ECU is outputting excessive voltage on the 5V rail, the Engine ECU has suffered an internal hardware failure and must be replaced.

5. 5

   Restore parameters

   If the Engine ECU (EDC) is replaced, you must use the appropriate Case IH Electronic Service Tool (EST) procedure to restore self-learning parameters and reload the engine dataset.

6. 6

   Clear codes

   Clear the fault codes from the module and run the machine to verify the repair.