03 Dodge Ram Quad Cab 1500 w/5.7 2wd auto 70kmiles.
Parked truck for 6 hours came back out and would not start. Not even crank. Turn key to start position and no noise etc. Cleaned batt Terminals, batt checked out ok aswell, Starter was tested and passed, replaced ignition switch(still no start). Swapped Relay, Also swapped #14 and #20 Fuses(still no start). Pulled relay. Getting Voltage at the #30 Terminal, and ground from the #86 Terminal(pcm). Jumpered the #30 Terminal to #87 terminal(starter) and truck started right up with key in run position. Truck also turned off with the turn of the key, but still not getting anything when turning key to run position. Only thing I am thinking is a break in voltage between key and relay, as the #85 terminal on relay does not throw voltage when the key is on the start position(should it be?) Any ideas on what else it could be at this point? Also truck would not start in neutral with the turn of the key either(so don't think it is safety switch), And since when I jumpered the terminals together to start the truck from the relay it was sitting in park and did not seem as if it was in gear. And no trans problems previously reported. Kinda frustrated at this point. And to top things off we had nice 60degree weather 3 days ago and now lol it is 14 degrees so I'm freezing my butt of standing out there scratching my head(haha).
Dandy testing. Jumping 30 to 87 proves the high-current starter circuit and medium-current solenoid circuit is working. That just leaves the low-current ignition switch circuit. The booboo is with pin 85. That is the ground side and should read 0 ohms to ground. The 12 volts when the ignition switch is turned to "crank" shows up on pin 86.
Check for 12 volts on 86, then check for ground on 85. The neutral safety switch is a good suspect. The same contacts are used regardless if it is in park or neutral.
January, 11, 2011 AT 6:34 PM
Yes I have already done this I am getting ground from the pcm and no voltage with the turn of the key to start position on pin 86. Is there a way to test neutral switch? It doesn't seem expensive so I might replace it for goo measures buuut I believe in if isn't broke don't fix it. And i'd rather test it first
January, 11, 2011 AT 7:37 PM
No need to look at the neutral safety switch if you already identified the missing voltage from the ignition switch. If you want to double-check that circuit, measure the resistance from terminal 85 to ground. You should find close to 0 ohms in park and neutral. You can also check it with a test light. Hook the clip lead to the positive battery post, then it will light up when you probe a ground circuit.
If you're not finding voltage on terminal 86, you can split that circuit in half by probing the clutch switch jumper wire. That might be a yellow 4" wire in a dark green 2-pin connector just to the left of the brake pedal under the dash. If you don't find voltage there in the "crank" position, look at the ignition switch connector next.
January, 11, 2011 AT 9:57 PM
Ok, great I will try that next. In the interim we just got blasted by a pretty good snow storm. Needing truck atm. Was wondering if I bought a hand held remote starter switch with push button engage, if I could clamp one end of the remote switch to the pos. Batt terminal and the other to a jumper wire running out of starter relay terminal #87 as a sufficient starting tool for the time being with out any ill effects to the relay terminals or PCM etc.
January, 11, 2011 AT 11:16 PM
You would be switching about 20 amps that way. If you connect it to pin 86 you'd be activating the relay, letting it do the switching.
It would be easier to just pop the cover off the relay, then squeeze the contact to crank the engine.
January, 11, 2011 AT 11:56 PM
Well I took 14 gauge wire, stripped the wire end and put it down inside the terminal #87, took the other end, stripped it and attached it to switch wire #1. Then took switch wire #2 and connected it to positive battery terminal. Pulled the trigger on the remote and truck started. Seems to work ok as I have tried a couple times and doesn't seem to be letting off excess heat or smoke. I was worried about the bypassing the fuses doing this causing possible high amps, however I am showing per my electrical diagram that the #87 terminal runs to the starter via a 14gauge wire. So the amps shouldn't be more than the system would normally be pushing correct? It'd be the same as jumping terminal#30(which has a 30amp fuse) to terminal #87. Maybe I should put an inline 20amp fuse in just for safety measures although I believe the switch has one already in it. Now that the truck is mobile again I can move it from my far corner of the drive up to my garage away from the weather to start checking more stuff. I will let you know what I find with the clutch switch jumper.