P1649-GLOW PLUG MODULE POWER SUPPLY CIRCUIT

P1649-GLOW PLUG MODULE POWER SUPPLY CIRCUIT

For a complete wiring diagram, refer to the Wiring Information.

Theory of Operation

The Glow Plug Module has the appearance of a large relay and is located next to the battery.The Glow Plug Module receives a signal from the Powertrain Control Module (PCM) to activate the Glow Plugs. The Glow Plug Module supplies power to the Glow Plugs and a ground path is provided through the body of the Glow Plugs. The Glow Plug Module communicates with the PCM over the (K330) Glow Plug Module Control circuit.

• When Monitored:

  Continuously with the ignition on and the Glow Plugs commanded on.

• Set Condition:

  The PCM receives 50 consecutive error messages from the Glow Plug Module Signal for a loss of the power supply.

1. CHECK FOR ACTIVE DTC

• Go To 2

• Perform the INTERMITTENT DTC diagnostic procedure. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).

2. CHECK THE (F344) FUSED IGNITION SWITCH OUTPUT CIRCUIT FOR AN OPEN/HIGH RESISTANCE

• Go To 3

• Repair the (F344) Glow Plug Module Signal circuit for an open or high resistance.
• Perform the PCM VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).
  

3. CHECK THE (Z933) GLOW PLUG MODULE GROUND CIRCUIT FOR AN OPEN/HIGH RESISTANCE

• Go To 4

• Repair the (Z933) Glow Plug Module Ground circuit for an open or high resistance.
• Perform the PCM VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).
  

4. GLOW PLUG CONTROL MODULE

• Replace and program the Powertrain Control Module in accordance with the service information.
• Perform the PCM VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).

• Test Complete.
• Perform the PCM VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).