1998 Explorer Anti Theft, no start

[bmeier]

Hello all, My dad has a 1998 Explorer. A few months back he had to replace the driver side door, due to a big nasty dent. So he put a replacement door on that he got from a junkyard. The "new" door has the Keypad on the outside. (original doors on truck do not). Truck ran fine until a few days ago, Battery was dead, he replaced with new battery and truck will not start. Nothing happens,( not turning over, no fuel pump),He also unhooked battery for an hour, he checked all fuses and relays as well. The anti theft system is preventing the truck from starting. He told me he "jump- started" it from underneath via the starter. I am far away and will be going to help him in a few days with some of my tools. I am thinking the new door might be "triggering" the theft system. I don't know for sure though. I am going to pull codes when I go there and I am going to unhook the wires to that door and unclamp the battery for 30 minutes to reset, I am then going to try and lock/unlock with key fob and try starting then. Any advice on this. I do not have access to the door donor vehicle for the default code on the alarm ecu either.

 

[koda2000]

It's not the anti-theft system preventing the truck from starting. Anti-theft only turns off the fuel injectors, not the starter.

You have an electrical problem. Possibly bad/corroded or dirty battery cables/terminals. Also check the mega fuse in the rear of the power distribution box.

 

[bmeier]

It's not the anti-theft system preventing the truck from starting. Anti-theft only turns off the fuel injectors, not the starter.

You have an electrical problem. Possibly bad/corroded or dirty battery cables/terminals. Also check the mega fuse in the rear of the power distribution box.

I was under the impression that the anti theft system disabled the fuel pump and starter, When you turn the key nothing happens, It does not try to turn over and the fuel pump is not audible. They have had issues in the past with the key fob and I have noticed that it seems similar in that regard to the no starting. Plus I don't know if it is a fuse ( I will test the fuse though, thank you for that input). The truck has never had slow or intermittent starts before and there is no corrosion on battery terminals and all grounds were cleaned and tightened to spec about a week ago.

 

[koda2000]

Power has to flow from the battery to the starter (which it apparently does as you were able to "jump start" the engine by jumping the wires at the starter). Power also needs to flow to the power distribution box (located near the brake master cylinder under the hood) When the ignition key is turned on power flows to the rest of the vehicle via the power distribution box, through the fuse panel located on the left side of the dash. When the ignition key is turned to START a rod move inside the ignition switch making electrical contact to energize the starter relay and solenoid(s). I believe the '98 still had a starter solenoid located near the battery mounted on the driver's side inner fender. Power is then sent to the starter motor to crank the engine over.

You are losing power somewhere. Power apparently isn't getting to the fuel pump relay either. This fuel pump relay should be energized as soon as the ignition key is turned to ON and the pump should run for about 2 seconds.

Are you getting power to accessories (radio, blower fan, wipers) when the key is turned to ON?

None of your issues has anything to do with key fobs, anti theft or door key pads. It's just electrical. If you have a VOM or even a test light you need to track down where you're losing power.

 

[bmeier]

Update, So I'll be able to look at the truck tomorrow. The fuel pump does turn on but truck does not start. I guess I'll start with doing a parasitic draw test. My dad replaced the ignition switch, battery, neutral safety switch and I think a relay or two, I'm not 100% on what else he has done until I get there. If there is something electrical preventing the truck from starting where should I look first?

 

[Turdle]

It might be a good idea to check all the fuses. This should help identify them for you. There are several under the hood and several on the driver side end of the dash , you have to open toe door to access them.


http://www.explorerforum.com/forums...eration-power-distribution-box-layout.180814/

After checking the fuses, if there is no resolution, then step back, and start from the beginning.

This is a very good thread for "no start" diagnosis.

http://www.explorerforum.com/forums...rd-explorer-engine-no-start-procedure.264205/

 

[bmeier]

Thank you for the info, I will post an update tomorrow when I start to work on her.

 

[bmeier]

Check engine light does not come on when truck is put into start position, All fuses , relays look good, I pulled the Pcm, also now it is blowing the fuel pump fuse. How do I bench test the PCM?

 

[Turdle]

Ok we need to back up a bit, because the fuel pump will not run without the check engine light illuminated, unless the check engine light has had black tape put over it, or has been pulled, or is burned out.

PCM sends signal to fuel pump. No check engine light when on means no PCM power.

I do not think there is a way to "test" the pcm. You should be looking for a short circuit in the fuel pump wiring.

At this point I think some damage was done with the jumper cable fiddling-----

 

[koda2000]

Let's start over...

What happens when you turn the ignition key to the ON position? Normally the instrument cluster should enter "bulb check" mode. In bulb check mode all the various warning lights (including the CEL) should be illuminated. Does the CEL come on?

When the ignition key is turned to the START position what happens? Nothing? Loud click(s)? Relay click?

 

[bmeier]

Alright, sorry guys lol, I know this is all over the place but after I looked at it Let me tell you what is going on. So as of right now when you turn key to start position all bulb lamps are functional. No clicks no noise , nada except for now a fuse is popping. I did pull the cluster off and I checked the CEL bulb, Bulb is good. No crank, no fuel pump activation but now it blows the Fuel pump/Pats mini 20 amp fuse. (all other fuses and relays are good) It was not blowing the fuse when I first started looking at it after hours of meddling around at the end of the day it started popping the fuse. I traced the wiring harness and did not find any shorts, I also pulled the distribution box and checked underneath and nada. I could not find any wiring schematics but I was getting power on 4 wires at the pcm connector plug (3 constant hot and 1 hot with key on) I also noticed key pad fob did not activate doors or function at all. (fob battery good). My mom told me within a week prior to this happening she did notice several mornings where it had slow starts. If the Pcm is bad could that be causing the fuel pump fuse to pop? Every ground point I could find I cleaned em all. The fuse popping did not start happening untill after we started meddling around. It started to short after I took out that 175 amp main at the distribution box. If i messed that up which I don't think I did, it appeared fine and came out and went back in without a hitch. if that were messed up would it blow that fuse? damn exploder....