Bad starter, bad connection, or bad ignition switch/neutral safety switch?

[redfishsc]

Good day gents,

My 99 Suburban C1500 (5.7L) has been failing to start lately. Battery has plenty of voltage, and swapping batteries (from my other truck) changed nothing, still fails to start.

The failure is just a single "click" and the Starter does not rotate. The click sounds like the solenoid engaging but I cannot say for sure.

Battery connections are fine. I have not yet inspected the starter connection, I will do that tonight.

Either way, I have to get this thing running by Saturday.

Can anyone advise me on how to know whether it's a failing starter or a failing switch in the steering column?

 

[454cid]

Good day gents,

My 99 Suburban C1500 (5.7L) has been failing to start lately. Battery has plenty of voltage, and swapping batteries (from my other truck) changed nothing, still fails to start.

The failure is just a single "click" and the Starter does not rotate. The click sounds like the solenoid engaging but I cannot say for sure.

Battery connections are fine. I have not yet inspected the starter connection, I will do that tonight.

Either way, I have to get this thing running by Saturday.

Can anyone advise me on how to know whether it's a failing starter or a failing switch in the steering column?

Well if you hear the solenoid clicking it's getting what it needs from the switch in the steering column. You can check it with a test light, and a helper turning the key, just to make sure it's not a relay that you're hearing.

Here's what I would do:

1 Check the wires at the battery. Remove the hoods/covers, and check for corrosion where the connector and wire interface. Batteries can leak, and the acid will travel down the wire strands.

2 Remove the wires from the starter and look for corrosion or mechanical damage.

3 Remove the starter, and test it on the bench, or take to Autozone/wherever for them to test it.

 

[RichLo]

^ Do what he said but before you remove it try tapping on the main starter body with a hammer first. If it starts you still need a new starter as the brushes are worn to the point of being unreliable but you've found the problem.

 

[454cid]

^ Do what he said but before you remove it try tapping on the main starter body with a hammer first. If it starts you still need a new starter as the brushes are worn to the point of being unreliable but you've found the problem.

Yes, this would be a good idea. I was actually doing that with my own truck. This does often require a second person, However. Someone will have to be turning the key while the starter is being hit.

 

[Schurkey]

I'm dicking with starter problems on my '97 K2500 7.4L.

1. There's an ordinary "cube"-style relay with four terminals, in the underhood electrical box on the left front fender, that triggers the starter "S" terminal. MAYBE that's the relay you hear clicking. Of course, that relay has to have adequate power "in", a good ground, an adequate signal from the ignition switch, and a good output wire. (all four terminals need proper connections)

2. That relay powers a purple wire that attaches to the starter solenoid "S" terminal. The "S" terminal needs proper voltage and current. This is the issue with my truck--that wire is corroded at the starter end. It's been repaired before with a 4--5 inch section spliced to the starter end, but I've cut back at least 8 inches and the wire is still corroded green. I'm going to have to find that wire in the harness across the top of the engine, and splice in ~3 feet or more of fresh wire in order to get back to copper-colored wire in the harness. Maybe I'll have to go all the way back to the relay box. This may--or may not--be the problem you're dealing with. Turn the key to "crank" and TEST THE VOLTAGE AT THE STARTER "S" TERMINAL to find out. You'd better have within a volt or so of battery voltage at the "S" terminal.

3. There's a bigass copper disc inside the starter solenoid. Very common for that copper disc to get "burned" spots on it, so that it won't transfer power from the battery cable lug to the actual motor windings. The copper disc and the copper contacts wear and degrade. MOST folks get a rebuilt starter rather than just replacing the starter solenoid. Again, a voltmeter will tell the tale--but it's a real ***** getting the voltmeter leads connected to the battery cable lug and the post or the cable going to the motor windings. A voltage-drop test would provide convincing proof of the solenoid "copper disc" failure.

+ voltmeter lead to the battery cable lug on the starter. - voltmeter lead to the motor winding lug or cable. Anything over 1/2 volt indicates excess voltage drop--solenoid is defective.

4. IF (big IF) the solenoid is engaging, and IF the bigass copper disc is still OK, the starter motor can still have a bad armature or stiff bushings.

5. Because it's so hard to get the test leads where they need to be, MOST folks will replace the starter if the cables look good and there's adequate power to the "S" terminal.