How can you tell if a glow plug is open?
Check the glow plugs for an open circuit. Pull the connector off the glow plugs. Use a test light and connect it to the positive battery terminal. Touch each terminal to a glow plug. Each should show a good ground. They can also be tested with an ohmmeter. Each should have less than .4-ohms, or very low resistance.
How to check for a glow plug relay fault?
Using a voltmeter, check for battery voltage to the glow plug relay main supply terminal. Have a helper turn the key on and check the opposite terminal for voltage drop. If there is a drop over a half-volt replace the relay. The relay is the main cause of failure under this code Check for power from the ignition switch to the relay with the key on
What should the voltage be on the glow plug?
It should have less than 0.5 volts. This is the wire that grounds the coil in the glow plug relay. Also listen for the relay to click when you cycle the key off and on. 4.If you don’t hear a relay sound or the voltage is higher than 0.5 volts, try checking for output voltage at the relay on the two large brown wires—one to each engine bank.
What happens if a glow plug malfunctions?
If the glow plugs malfunction they will not provide the additional heat that aids in diesel combustion, which may cause the engine to experience misfires. The misfires may cause a loss in power, acceleration, and even fuel efficiency.
How can I tell if my glow plug is working?
Observe if the glow plugs are getting the power they require by connecting a test light to the plug. If the test light lights up, the plug is receiving power. Evaluate whether or not the relay is able to supply the power required to start the diesel engine by testing the ohms of the circuit with an ohmmeter.
Why is my DTC glow plug not working?
Both DTCs P1391 and P1393 together will set when the monitor indicates that all eight glow plugs are not being powered. An open in all glow plug circuits, the glow plug relay, glow plugs, fusible links or all three monitoring circuits could be the possible causes.
What should the EOT be for a glow plug?
EOT temperature below 55°C (131°F) for F-Series or 30°C (86°F) for Econoline. With the key on, engine off, measure voltage between center terminal of glow plug shunt and battery ground. If voltage is not present for at least 30 seconds, replace glow plug relay.
What to do if your power stroke glow plug is not working?
CLEAR DTCs and RETEST. Else, if voltage is greater than 10.5 volts, perform KOEO (Key On Engine Off) On-Demand Self Test and retrieve Continuous DTCs. If DTC P0380 is present, DTC P0380 is set when the PCM detects a malfunction in the glow plug relay control circuit. Possible causes: open fuse (F-Series – Fuse 30, Econoline – Fuse 8)