New Holland 1808 – Engine ECM: Burner Glow Voltage: Out of Voltage - High

The Engine Control Module (ECM) has detected an abnormally high voltage in the electrical circuit for the aftertreatment burner glow plug. This heating element is used to raise the temperature within the aftertreatment system to facilitate the regeneration of soot from the Diesel Particulate Filter (DPF). A high voltage reading suggests an electrical fault, most commonly a short circuit to a power source.

• Workmaster
• PowerStar
• T4
• T5
• TD5
• L225
• L230
• C232
• C238
• B95C
• B110C
• TC35
• TC40
• TC45

1. 1

   Verify system voltage using a multimeter. With the engine running, charging voltage should typically be between 11.5 and 13.5 volts under steady conditions. A reading consistently above 14 volts could indicate a faulty alternator or voltage regulator.

2. 2

   Inspect the wiring harness for the glow plug system, from the control module to the individual glow plugs. Look for signs of corrosion, frayed or melted insulation, and loose connections at the glow plug controller, harness connectors, and the glow plugs themselves.

3. 3

   Test the voltage output from the Glow Plug Control Module (GPCM) to the glow plugs during the pre-heat cycle (when the key is first turned on). If the output voltage is excessively high, it may point to an internal failure of the controller.

4. 4

   Test individual glow plugs: Perform a resistance test by measuring between the plug's terminal and the engine block (ground). A good plug is 0.5-2.0 ohms; an open circuit (infinite resistance) or a direct short (zero ohms) indicates a failed plug. Also perform a voltage test with the harness disconnected to check for voltage at the connector when the ignition is turned on.

1. 1

   Disconnect the Battery

   Disconnect the negative battery terminal to ensure safety before beginning any repair.

2. 2

   Address charging system or wiring faults

   If diagnostic checks revealed a faulty alternator, voltage regulator, or damaged wiring, repair or replace these components first.

3. 3

   Replace faulty glow plugs

   Apply penetrating oil to the base of the glow plugs and allow it to soak. Carefully disconnect the electrical connectors. Using the correct socket size, remove the old glow plugs. Clean the threads in the cylinder head before installing new plugs. Thread the new glow plugs in by hand, then tighten to the manufacturer's specified torque. Apply dielectric grease to the electrical terminals and reconnect the wiring.

4. 4

   Replace Glow Plug Control Module

   Locate the glow plug control module, disconnect the electrical connectors, remove the mounting hardware, replace the old module with the new one, and securely reconnect the electrical connectors.

5. 5

   Perform final system check

   Reconnect the battery. Turn the ignition on to allow the glow plug cycle to run. Start the engine and verify that fault code 1808 has cleared from the display.