Just got 4.2 stabbed back in, truck has been sitting for a year and a half. The instrument lights and everything work like they're supposed to but it won't crank over. I can jump the solenoid, and it turns over fine, just not with the key. I tested for 12v on solenoid wire while turning key and got 0v. Do these era trucks have any kind of security? Only other thing I can think of, would be a clutch switch (its a manual), or mouse damage.

Any other ideas?

Frank

 

Stick or auto tranny?

No PATS from the factory on a 98, but there was an optional anti-theft variation (RAP) that included a starter interrupt relay. If that system is installed and triggered, the lights should be flashing and the horn should be blowing.


Check fuse F21 under the dash as the starter signal goes through it from the key switch.

 

Sorry for delayed response....

It's a stick (or manual whatever suits). No horn, no flashing lights, so no rap on this one. I checked fuse #21 (15amp) under the dash, not blown. Could you tell me the what the path is to the solenoid trigger? If I had to guess, I'd say it goes from the key switch through the fuse, through the clutch safety switch, to the solenoid? Am I missing another component? Thanks for your help

Frank

 

You got it.

Switch (R/LB) to F21 (W/LB) to clutch pedal switch (DB/O, TR) to the starter relay.

 

Awesome! I thank you, kind sir! I'll report back once I figure it out whenever I get a minute to mess around with it (hopefully this weekend).

Frank

 

Messed around with it for while, here's what I'm finding:

There's no W/LB going to the clutch switch. There is a DB/O though. There's 6 wires total going to the switch. There are 2 W/PK wires going to the switch, which both have power when the ignition switch is turned to start. I tried unplugging at the clutch switch, and jumpered the W/PK with the DB/O wire, and tried to start. Still nothing.
What do the rest of the wire go to at the clutch switch? If I've got the wire colors correct, I was thinking about just bypassing the switch so I can still start it without using a toggle switch, which is dumb in my opinion. I can live without safety switch....
Any ideas/input?

Frank

 

so ther are two styles of starter systems, one has the interlock which prevents the starter from cranking. do you have a "theft" light blinking in the instrement cluster when you try to start it? if there is a problem with that system like the key is bad or the transponder that reads the key it wont beep horns or anything like that but it will keep it from cranking over. also which solinoid are you jumping to crank it? the one on the firewall or on the starter. I have had the one on the firewall develope corrosion on the screws that hold it to the firewall and it keeps it from cranking over. sometimes it helps to remove the hold down screws and scratch the panit away , reassemble it and re try it. either way measure the voltage to the tam/ with red wire at the solinoid while someone hols the key to start, measure the voltage there. if nothing is there then it may have gotten some corrosion on a pin somewhere. here at the dealership we have to trace them down, good luck.

 

You're a week late on the anti-theft idea...read above. If he's not getting the power feed from the ignition switch to the starter relay, the mounting screw for the relay doesn't matter.... He already tested the tan/red wire, read above.

Double check the 6-wire connector on the CPP. It should have two W/PK wires on pins 1 & 5, DB/O on pin 2, LG on 3, T/LB on pin 4, and GY/Y on pin 6. The CPP is a 3PDT switch. When the clutch pedal is pressed, pins 1-2, 3-4, & 5-6 are made. We're interested in the 1-2 since that is the feed to the starter relay It goes through several connectors and changes to a tan/red wire at C172.

 

Yes, sir...those are the colors. I did try to jumper 1 and 2 the other day, no difference though. If you say there's several connectors in between, it would seem there's one unplugged from where I removed the engine. I'm usually really thorough when I r&r engines, but nothing is impossible, I suppose. I do know for a fact that it started and ran before I took it apart. Does that clutch switch supply signal voltage to the fuel pump relay, or is that not related? What are the other circuits on the clutch switch?
The only thing that I know I couldn't figure out where it went, is the long yellow vacuum line (still trying to figure that one out).

I will go over it with a fine tooth comb next chance I get...there's gotta be a connector unplug...i just didn't think there was one for the starter solenoid trigger.

I appreciate the responses...now I just gotta connect my eyeballs to the stimulated gray matter!

Frank