First off, I want to say thanks to everyone who has helped to this point. I've been working on this problem since I tried installing my DP tuner on Friday

https://www.ford-trucks.com/forums/8...-question.html

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After trying advice from several members on here & working back & forth with Dennis @ ITP. I'm still at square 1.. won't start.

My current symptoms are.. Cranks, oil pressure builds up, no smoke from tail pipe. Some of the lights on the dash come on ...battery, low oil pressure...parking brake light, door ajar & the ABS light & seat belt light & low fuel comes on, then goes out.. The WTS light does not come on AT ALL...Fuel gauge moves & the volt meter jumps up to about the middle of the gauge. While I am cranking, the tach does not move.

I am 99% sure the fuel pump is not kicking in. Dennis had me unplug the map sensor, the CPS & 2 others.. one in the drivers side head area & one below the HPOP (don't remember the names) The WTS still did not come on when the key was turned on.

I tried a DPC-422 CPS from my nephews truck & it did not work.. His truck currently has a blown motor, so it then had me questioning that it may have had something wrong with it. I then went to a local salvage yard & got ANOTHER DPC-422, but the results were the same.. No different.

They salvage yard just cut the wires & gave me the harness end & all.. I took that plug & figured out how to take the end off the harness to see the pins then I did the same with my trucks harness.I looked thru the firewall & compared the two plugs.. all the female pins appear to be there & pushed in ok...

I also have a remote starter & I checked all the wires for something pulled apart.. short of untaping everything I can't see anything. I even pushed the starter button & the truck goes ahead & trys to crank over, just like usual.

I switched the relays under the hood (PCM power module? & blower motor) the blower runs with either one... I changed, checked & swapped NUMEROUS fuses.. I wiggled wires...still nothing. The biggest thing that baffles me is, that when I pulled the 2 20 amp fuses in the box under the hood ( # 19 & 24 I think,,, PCM power & fuel pump if I recall right) I get NO voltage reading with or without the key on.

I did buy a new CPS (gray) but have not changed it yet.. The only other thing that makes me wonder is, the truck is sitting nose downhill in my driveway. As it sits, it shows below 2 quarts on the dipstick. I just checked the oil a few days ago & it was full & its been run less than 100 miles, so i'm assuming it just because of the angle that its sitting at. That couldn't have any effect could it???

This is getting VERY frustrating as I am now 2 full days into this & still am no further ahead..

 

On my late '99 there is a large fuse panel under the hood that has some Maxi-fuses.
I accidentally blew one of those one time by shorting a wire.
That fuse powered the ECU and the WTS like would not come on = dead truck.
Had to swap a fuse from somewhere else to get it to start, drive to NAPA and buy another fuse.
It was one of those big 30 or 50 amp fuses too.

 

IMO, it sounds like the PCM is not getting connected right. I would pull the PCM under the fuse box, unhook your chip, re-clean the connection on the board where the chip plugs onto, and reinstall. Make sure that the connector inside the engine bay that connects to the PCM is tight and bolts up. I had a no-start, no Wait to Start light situation as well. I think that if that isn't plugged in then a lot of start doesn't work.

 

I was really thinking you would have found something simple to explain this by now. If you turn the key on and pull the PCM relay, are any of the slots the relay plugs into showing voltage? If so, which ones?

 

I've checked & double checked the fuses.. they are all good. After the 1st day, I took the tuner out & have been trying to start it with just the PCM. I've examined the plug numerous times & can't come up with anything..

 

That's one thing I didn't try.I was kinda intimidated buy the multiple prongs & was afraid I would short something out & make matters worse.. if that's at all possible !!!

 

did you check fuse #30 under the dash?

 

IIRC, doesn't the fuse for the fuel bowl heater can short out and cause a no-start and no Wait to Start symptom? #30 fuse or something like that. Just thinking out loud.

 

Anyone have any idea about the 2 fuses I mentioned under the hood in the power distribution box... I just went & got the book,, # 19, 20a.. fuel pump motor, PCM & # 24 PCM power 20a When I pulled the fuses & placed a meter on them, I got no readings ( key off or on) Should they be hot at some point? I'm just baffled.. do they supply power TO the PCM & fuel pump or does the PCM supply power to them some how???

 

Yep, I bought one of those big kits with tons of fuses & a fuse tester... I'm pretty sure I replaced every fuse under the dash that I thought would have something to do with the PCM

 

Don't get thrown off by the no WTS light guys. That's just one of the items that is not powering up. The PCM is not waking up with the key in his truck. WTS light is out, fuel pump does not come on with the key, IDM will be dead and my guess is the OBDII connector is out as well.

Gregg, just pull the relay and probe the slots the relay plugs into. I'm trying to find the wiring diagram for which post does what. Seems like there's a power source, ignition pole, power out pole and something else.

We talked about those diodes earlier today. I just ran across something in the manual on accident (that's how I find most of the electrical stuff in the manual) and apparently the diodes must be installed a certain direction since they only flow current one way. The diagram in my manual shows the PCM diode in the lower right and the AC clutch diode to the left of it. It shows arrows on the diodes that point to each other. If they are not the kind that can only be plugged in one way, and you might have put one in backwards, it's worth checking into.

Edit: Those fuses are dead because something is not sending power to them. That's why I'm wanting to see if there's power at the relay. I think the relay sends the power to those fuses.

 

I remember reading that somewhere.. But I never found a burnt out fuse.. So I never looked any further into that...

Also, I'm not sure if I mentioned this in one of my other threads.. But I had NO signs of any problems prior to this.. It was running great when I pulled it in the driveway Friday

 

I'll go out & check the relay slots now.. Dang, I wish I had a garage big enuf to fit my truck in or the temp would raise up to at least 70 !!

I pulled the diodes out earlier & checked them with my fuse tester.. they appeared ok & you are correct.. the prongs face different directions & can only be plugged in 1 way..

 

I'm not sure how to explain this, but here goes.. First off, I'm not very electrc savvy, so I may have done something wrong, but I placed the black probe to ground & then tested the 4 contacts with the red probe

....... _ (2)

I (1) [](5) I (3)

........ I (4)

Looking at the plug, there's 5 prongs.. (forgive my diagram, its the best I could do)

#1 & #2 prong are never hot
# 4 prong is always hot

#3 prong is hot on the blower relay when I turn the key on, but is never hot on the PCM Power relay
# 5 prong doesn't appear to have anything where it plugs in (as best i can tell)

 

I can't find the stupid diagram for the 01. I had one saved for the 02. Let's hope they're the same, or at least use the diagram to determine which post is hot.

You might also check the PCM diode location under the hood the same way. I stumbled across a diagram that looks like the power has to go through the diode before it goes to the relay.

Here's some info. Now let's hope someone that understands all this looks at it and suggests where to check next.