Iveco 032B – Engine Control Unit (EDC / Engine ECU): Glow Plug Relay Control Circuit Malfunction

The engine computer has detected an electrical fault (short to ground, short to battery voltage, or open/broken circuit) in the circuit that commands the glow plug relay to turn on. This prevents the glow plugs from operating, leading to difficult cold starting, rough idling, and excessive smoke on startup.

• Iveco Daily
• Iveco Eurocargo

1. 1

   Check the EDC and Pre-heating Fuses: Locate the fuse box and check the specific EDC fuse (often 10A, e.g., Fuse #24) and the maxi-fuse for the glow plug circuit.

2. 2

   Inspect the Wiring Harness: Carefully inspect the wiring between the EDC and the glow plug relay for exposed copper, breaks, or shorts to the chassis caused by chafing from the plastic corrugated wire conduit.

3. 3

   Check EDC Connector Pins: Check the wiring at the EDC connector (specifically pin B42) to find any short to +Batt, short to earth, or break in the circuit.

4. 4

   Test the Glow Plugs: Use a multimeter to test the resistance of each glow plug, as a completely shorted glow plug can cause the relay or fuse to blow.

5. 5

   Check the Coolant Temperature Sensor: Verify the sensor is functioning correctly, as the EDC relies on it to determine if pre-heating is needed.

1. 1

   Disconnect Power

   Disconnect the negative terminal of the vehicle's battery to prevent electrical shorts during repair.

2. 2

   Locate the Relay

   Find the glow plug timer relay. On most Iveco Dailys, it is located in the engine compartment fuse/relay box near the battery, or mounted on the firewall.

3. 3

   Repair Wiring

   If your diagnostic checks revealed chafed wiring in the conduit, cut out the damaged section. Use silver solder and heat shrink (or high-quality weatherproof crimps) to repair the wires.

4. 4

   Replace the Relay

   If the wiring is intact but the relay has failed internally, unplug the electrical connector from the old relay, unbolt it from its mounting bracket, and install the new OEM relay.

5. 5

   Reassemble and Clear Codes

   Reconnect the battery. Use an OBD2 diagnostic scanner to clear the 032B fault code from the EDC memory.

6. 6

   Verify Operation

   Turn the ignition to the 'ON' position (without starting). Verify that the glow plug light illuminates on the dash and turns off after a few seconds. Start the engine to ensure the cold-start issue is resolved.