Ignition switch

YODA82

MEMBER
2008 GMC CANYON
3.7L
5 CYL
2WD
AUTOMATIC
165,000 MILES

Over the last couple months sometimes my truck doesn't want to turn over. Lights and everything come on but the engine won't turn over. Not even a click or anything. Then about once a week or so I'll go to start it in the morning and my battery will be completely drained. I get a jump and it starts right up with no issues. I've had the starter, alternator, and battery checked. All is good. I'm starting to think it might be my ignition switch starting to go bad. Any advice or thoughts would be awesome please.

1 Reply

JDL

MECHANIC
16,098 POSTS

Note the diagram, starter circuit with automatic transmission. Any applicable trouble codes? With intermittent issues have to test when problem is ongoing, it could be any number of issues? The starter relay has two sides, switch side, which is left side in the picture, and the control side, right side in the diagram. When problem is ongoing, pull the relay, use test lite between cavities 85 and 86, key in the crank position, does the test light come on? If so, you got voltage and ground on the control side, that's good.
The switch side of relay, see that fuse, check for voltage on the fuse, use test light, hot all the time. Test when problem is ongoing. With relay unplugged if you use jumper wire between cavities 30 and 87, the starter motor should crank the engine. If you try this make sure transmission is in park or neutral and parking brake is set. That doesn't mean it will start.
https://www.2carpros.com/articles/starter-not-working-repair
Repair guides at top of page, a lot of links for different problems. Check it out.

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