Fusible Links - Testing

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Fusible Links - Testing
Each glow plug has a fusible link that if the glow plug fails will blow. Often there is no visual indication that the fusible link has failed.
To test:

Remove all glow plug wires.

For safety, disconnect the battery, meter damage may result if the meter is attached and voltage is applied at the same time.

From glow plug wire 1, test the resistance to glow plug wire 2, it should read zero ohms. If not zero, go to step X.

From glow plug wire 1, test the resistance to each of the remaining glow plug connectors, each should be zero ohms (shorted).

Any glow plug wires that read resistance probably have blown fusible links, or bad connections (usually at the controller).

X. From glow plug wire 2 test resistance to glow plug wire 3. If it reads zero ohms, use glow plug wire 2 instead of wire 1 in step 4, above. Goto step 4.
Alternate method, measure the resistance between each glow plug wire and the glow plug controller *output* terminal. Each wire should read zero ohms. This method requires removal of the inner and outer dog house covers. Use caution to make sure you are measuring from the output terminal, and not the input terminal--the output terminal has two larger connectors one with two wires (one is the glow plug light) and the other will have one wire. The glow plugs are arranged in two banks of four.
Peter H.

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