My sons 81 SD recently failed to start for him one night after work. So I took my tool box and jumper cables to see if I could get it home. In this particular case the engine was not turning over at all, only the glow plug relay was cliicking. So I did not know if it was the starter solenoid or the key switch which go bad in these things.

Here are some steps to diagnose starter problems and get you home:

Find the black plastic wire junction box normally located on the right fender.

The small purple wire is coming from the ignition switch.

The other wire connected to the purple wire is going on to the starter solenoid.(with a meter you should be getting 12VDC here during start)

If you are getting 12VDC during start here, your starter switch is good and chances are your starter or solenoid on the starter is bad. Just CLICKING sound is probably sticking solenoid. GROWLING noise is probably starter or low BATT charge.

If you are not getting 12VDC at this juction you have an ignition switch problem.

An easy way to bypass the switch is to diconnect the purple wire with the wire going to the solenoid, turn the key to the start position, jumper the wire that is connected to the purple wire to the POS post of the battery and the car will start and get you home where you can replace the switch housing or tumbler or both.(very easy jobs)

Tools required - phillips screwdriver and jumper cables

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I LOVE CATS....AND FRIES

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