Starter issues and other electrical oddities (1 Viewer)

[Sputnik]

Hi everyone,

This is my first post so please just bear with me, here is the story.

I have been having problems with the starter in my '97 land cruiser. When I go to start the truck, it will not crank. The issue is intermittent, but it seems to happen when the engine is warm. If I let it sit overnight, it starts right up. I replaced the starter with a re-manufactured Denso unit thinking the starter was bad, but the problem persisted.

First I checked the fusible link, all good there. Battery terminals and ground are good as well. Next I tested the new starter by jumping the signal wire on the solenoid to the positive terminal on the battery. The engine cranked, so the starter was good. I turned the key to the "on" position and used the jumper to crank the engine. This is when it started to get weird, because the engine started and ran fine, but now the BRAKE, A/T OIL TEMP, and oil light on the dash were illuminated. However, when I put the truck in reverse, the lights went off! I put it in neutral, the lights came back on. So basically R, D, 2, L = no lights. P, N = lights on. I have a feeling this is closely related to my problem, I'm just not sure how. In addition, the A/C compressor only runs if the lights are off. All other electrical works fine regardless of what gear it is in.

I crawled under the truck to investigate the wiring near the transmission/transfer case and found nothing wrong (that I could see at least). NSS wiring also looked good but I have not ruled this out yet. A while back I had to re-wrap part of the wiring harness that runs by the EGR because that was melted, but I'm not sure if it is related to these new problems in any way.

What else should I check?

 

[Pascoscout]

When the harness melted are you sure none of the wires ended up getting fused together?

Have you tested your ignition switch? Make sure that it's sending power to the right areas based on switch position.

 

[SUMMIT CRUISERS]

A couple recommendations with the issues here. #1 the starter ignition wire is degraded to a point of inadequacy. Do the Ford Solenoid upgrade and that will fix the no start issue. #2 the NSS barrel connector needs to be inspected for corrosion. This can also affect starting but more so issues related to which position the gear selector is in.
Not sure about the AC compressor issue. Has to be a wire shorted.

 

[Sputnik]

I ended up checking the ignition switch a few weeks ago trying to fix something else, but I guess it wouldn't hurt to check it again. For the last harness repair, the area was right near the injectors/egr. It had not been touching the EGR like most of the threads I saw. My problem was a little farther up, near the fuel rail. The injector wires were resting on the valve cover bolts and they had worn through the insulation. I electrical-taped the bare wires, covered them in some hi temp wire insulation, and zip tied them out of the way. No telling if those wires grounding out on the valve cover bolts didn't fry other parts of the harness though...

I will have a closer look at the connector on the NSS today. I have no idea how the A/C wiring ties into the rest of the electrical, but I do know that if the engine coolant temp gets too high it will not let the A/C compressor run, so it is most likely related...

 

[Sputnik]

Here are some video clips that might help with my explanation

 

[Sputnik]

I got working on the truck again yesterday...

I removed the NSS, rebuilt it, cleaned the connectors, and re-installed. Next I checked the ingition switch, that appears to be working too.

I have been studying the wiring diagrams trying to debug the electrical system. This diagram shows that the NSS, A/C amplifier, and ECM are tied into the ignition/start switch, which explains why those systems were affected. Now I just have to figure out why the dang thing won't crank every time!

 

[Sputnik]

The ignition switch turned out to be working intermittently, so I had to bypass it. Apparently the it is prone to wearing out over time and even though it technically sends 12 volts to the starter, the connection that makes internally is flakey and is not good enough to trigger the starter solenoid. When I check the starter signal wire with a volt meter (not connected to the starter) it's fine. As soon as I connect the signal wire the voltage drops significantly. I didn't have time to find a new ignition switch, so I added a momentary switch next to the steering wheel which I wired to a relay that goes directly from the battery to the starter solenoid. This let me drive the car until I can figure out how to find another ign switch. As far as the A/C compressor not running and those lights flickering on the dash, I figured out why they were acting up. When the key is in the "START" position, the A/C compressor is supposed to turn off and those light on the dash are supposed to come on. The ign switch acts as if it is stuck in the start position (all the time) just enough to trigger those.