1997 1500 5.9 magnum
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Joined: Apr 2010
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From: Clayton MI
Just think about it as water flow. Power goes to the ignition switch, when you turn the switch to Start, it send power to the starter relay control circuit. The other side of that circuit goes thru the park/neutral switch, and then to ground. If you hear the relay click when you turn the key to start, that part of the circuit is doing it's job. If you don't, then verify you actually GET power to the relay from the ignition switch, when it is in the start position. (Pin 85, I think.....) If you get power, then make sure you are getting a ground, (pin 86, though I may have those backwards, check the wiring diagrams to verify.) If you don't get a click from the relay, one of those two aren't workin' right. (or, the relay itself is bad.... test that by just swapping it with another relay. I think they are all pretty much the same there.) If you DO get a click though, then verify you have power at pin 30. That should have power at all times, regardless of what you are doing with the key. Pin 87 goes down to the starter solenoid. Need to see at least 9 volts getting down there to properly trigger the solenoid.
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Just think about it as water flow. Power goes to the ignition switch, when you turn the switch to Start, it send power to the starter relay control circuit. The other side of that circuit goes thru the park/neutral switch, and then to ground. If you hear the relay click when you turn the key to start, that part of the circuit is doing it's job. If you don't, then verify you actually GET power to the relay from the ignition switch, when it is in the start position. (Pin 85, I think.....) If you get power, then make sure you are getting a ground, (pin 86, though I may have those backwards, check the wiring diagrams to verify.) If you don't get a click from the relay, one of those two aren't workin' right. (or, the relay itself is bad.... test that by just swapping it with another relay. I think they are all pretty much the same there.) If you DO get a click though, then verify you have power at pin 30. That should have power at all times, regardless of what you are doing with the key. Pin 87 goes down to the starter solenoid. Need to see at least 9 volts getting down there to properly trigger the solenoid.
Administrator
Joined: Apr 2010
Posts: 87,479
Likes: 4,223
From: Clayton MI
At the relay, pin 30 should have a constant 12 volts, regardless of key position, pin 85 (or 86) should have power when the key is in the start position. Pin 86 (or 85.....) should go to ground, so long as the trans is in park, or neutral. The relay puts a jumper between pin 30, and pin 87, which goes down to the solenoid. It's actually a fairly simple circuit, see where the failure is.
