1996 F250 PSD, No Start

[justincollier]

I looking for some help on an issue I have been having with my 1996 F250 PSD not starting. The problems started about 3 weeks ago. I noticed the truck not starting on the first turn of the key. It would just click, like dead batteries. Turn the key back, try again and it would start. It would crank slower than normal, but would fire. This happened a few times. I added wiggling the battery cables (they are tight) to the mix, and the truck would start. Two weeks ago this trick quit working. I had a co-worker give me a jump, and the truck started. Drove it home, disconnected the cables, cleaned the terminals and cables with a wire brush, and tested voltage with a multimeter. I am getting a constant 12.7v on one, but the other bounces between a low of 10.5 to 12.6v. I thought this battery had a dead cell. So, I had this battery tested at Wal-Mart and AutoZone. It read 12.9v at Wal-Mart and 12.7v at AutoZone. Not satisfied, I took both batteries to O’Reilly Sunday and had them load tested. Both batteries passed. I had the starter tested yesterday (it is 14 months old) and it passed. The voltage regulator in 14 months old and the battery cables are 18 months old. The alternator is about 4 years old. I also did a visual check of the fuses under the dash and hood and nothing in blown. Now, I can’t get the truck started with a jump. Turn the key and click. It acts like the battery/batteries are dead, but they have passed two voltage checks and a load test. If anyone has any ideas on what to check next, or advice on this situation, I would appreciate their input.

Thanks,
Justin

[okney1lz]

Starter Relay? Jump it and see if it starts no problem. Could just be getting weak.

[Gypsum]

x2 on the starter relay if it is clicking. You can terminal arc the post with a insulated screw driver or an insulated tool. Mine went out and tested as stated and started up. Replaced it and I was good to go. One problem.....in the process I must have burned up my tach. Now this is an expensive $$$$ fix.

[justincollier]

Pardon the ignorance, but is the starter relay the same thing as the voltage regulator that is mounted on the inner passenger side fender?

[Gypsum]

Justin, no ignorance here. This site should be for DIY and professionals alike. I have attached a pic of the relay. This is an easy place to start.

[madpogue]

The starter relay is JUST the starter relay. The voltage regulator is built into the alternator, and isn't part of the starting circuit.

Jump the two big terminals (see pic ^^^^) to bypass the relay. NOTE: If you have a manual transmission, this BYPASSES the clutch safety. DO NOT DO THIS unless you have the parking brake set (and/or one or more wheels chocked) and the transmissionin NEUTRAL. Sorry about all the upper case, but a guy in this area recently goofed this up; jumped the relay with the truck in gear, the truck lurched, pinned him between the bumper and the garage wall, and, well, it was a Very Bad Day. Belt-and-suspenders -- be sure you're standing BESIDE the truck when you do this.

[justincollier]

Thanks guys. I will give that a try. If I understand correctly, there are two starter solenoids. The one on the inner passenger fender and one on the starter. I hear a clicking at the starter, but nothing and no movement on the solenoid on the inner fender.

[stroked92]

it could just be the wire frome the solenoid to the battery i had the same problem on my 97

[madpogue]

Technically, the one on the fender is a relay, not a solenoid. Yeah, there are gazillions of listings calling it a "solenoid", just like with the glow plug relay. But a solenoid physically actuates something _other_ than an electrical circuit. In this case, the relay on the fender simply completes the circuit down to the solenoid on the starter; the solenoid down on the starter turns on the motor, but it also moves the gear into position with the flywheel ring.

In any event, if you're hearing a click down on the starter, then the current is at least getting that far. That _usually_, but not always, means that everything "upstream" (key switch, wiring, fender relay) is okay. But it isn't always the case; it could be that the current is getting there, but is weak. The "jump" test recommended by okney would narrow that down.

It could also be a weak connection; bad connection at one of the battery terminals, or one of the battery grounds, or at the starter itself.

[justincollier]

So when I jump the two large lugs on the starter relay, that should bypass that relay and if that relay is the problem, the truck should attempt to start? I thought I also read somewhere that you can attempt this with an insulated screwdriver, is that correct? I just want to make sure I am understanding correctly so I don’t short something or injure myself. Jump the two large lugs, not the small one that runs to the ignition switch?
BTW, thanks madpogue for the reminder on the manual transmission, as that is what mine is.