You would need to check the glow plug timer circuit and the fuel supply. Diesel glow plugs can wear out. Make sure the "Ready light" is working and that you hear the timer cycling. Usually the lights will dim as the power goes to the glow plugs.
The glow plug wire can be checked with a Voltmeter inserted on a wire from the Relay timer. The glow plugs are tested when they are removed from the engine. If you get this far, you can use battery cables to test them. They can melt. Ask for more details about proper procedure.
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You would need to check the glow plug timer circuit and the fuel supply. Diesel glow plugs can wear out. Make sure the "Ready light" is working and that you hear the timer cycling. Usually the lights will dim as the power goes to the glow plugs.
The glow plug wire can be checked with a Voltmeter inserted on a wire from the Relay timer. The glow plugs are tested when they are removed from the engine. If you get this far, you can use battery cables to test them. They can melt. Ask for more details about proper procedure.