MK4 Coyote electric problem, need advice

[armydoc]

I uploaded a video of my problem and describe/show the situation but here is a little more background.

The video is here:
http://youtu.be/vwjB50ZaCqw

I bought some aftermarket LED lighting to illuminate the foot boxes and installed it, running it to one of the supplied FF toggle switches. I spliced the grounds into an existing ground wire and ran the positive lead to the "courtesy light" wire, as shown in the video. With accessory power turned on, I flipped the toggle switch and immediately all the lighting on my FF Vintage gauges was fried and the car wouldn't start. I was able to replace the Coil/EFI fuse and the car will start, but now I can't turn it off with the key. When I turn the key off, and even if I remove it, the car continues to run. I have to use a screwdriver on the inertia button to get it to stop. Even when I do that, the odometer stays on. I have to remove the fuse and put it back in to get the odometer to turn off.

In addition to being depressed about ruining my $700 vintage gauges before I ever had a chance to see them at night, I'm also confused about what problems I may have caused. I was having a blast building this car up until this point and could really use some advice.

Jim

[2bking]

It doesn't seem like you could have fried all that just by wiring into the radio lamp. I suspect you tied into the wrong wire and fed 12 V into a signal circuit. It could be that the gauges are not destroyed but you have a relay stuck energized. There is a power distribution box that should switch off various circuits when the ignition is turn off. Have you observed the lights on that box with the ignition off and on. Try removing your new wiring and disconnect the battery. Then reconnect the battery and see if sanity returns. Otherwise, draw circuit diagrams to see what might be connected to your new wiring. I'm a ME not a EE so others will be able to help more.

[Jester]

Funky

2x as suggested by 2bking. I would return the system to the state prior to having the issue, disconnect the battery and reconnect the battery, check for proper power at your gauges, ignition, , etc, etc. I also installed under dash and trunk LED lighting and connected to the curtesy lighting wire on the Ron Francis harness (I need to double check the proper name of this circuit) and I had no issues with proper functionality. I would also double check the ignition switch for proper functionality in the off position.

[carlewms]

Jim,

I agree with King ... Start by removing the new wiring completely and make sure that the spliced areas are taped over to prevent any shorts.

For the engine to keep running the EFI and Ignition box are still getting power with the ignition switch in the off position. I would check the ignition switch to make sure nothing happened to it. I would check the leads to the EFI ECU and the ignition box to make sure they are not still connected to power somehow.

Like King says if you have any relays providing power to these components , check them to make sure they are de-energized.

Carl

[armydoc]

Thanks guys. I've been working but I have Tuesday off and will try this and double check all the wiring. Is it possible that the ignition switch itself could be damaged? It seems that it's just a mechanical connection to open/close a circuit right? If resetting the wiring and disconnecting/reconnecting the wiring doesn't help then I will order a new ignition switch.

[dforthof]

Army,
The FFR vintage gauges have an LED driver for the dimmer function on them, it's the little heavy box that the dimmer wheel hooks up to. This is a PWM box, it outputs a pulse signal to the dimmer lights in the gauges because LED's dim with pulses, not lowered voltage. It's possible that you fried (closed the circuit) in this box, which would backfeed PWM voltage onto the courtesy circuit when the ignition switch is off. A PWM voltage on that circuit with no regulation would cause all sorts of funky things to happen since it feeds into the main B+ feed for the car. I would disconnect this box and give it a try.
Another question, did you wire your car exactly like they say in the Coyote installation manual with the RF wiring harness? This will help me to help you.

[armydoc]

As suggested I removed the courtesy wires and ensured that any spiced wires were taped or covered with heat shrink. I then unhooked the negative battery terminal and after a few minutes reattached it. Now I cannot start it again. When I turn the key to the accessory or on position, the gauges "burp" a little bit, they all move a fraction of an inch and return to normal but the fuel pump doesn't kick on and the car does nothing if I turn the key as if to start it. I made sure that the inertia switch wasn't engaged or unengaged and I also rechecked all the fuses, specifically the EFI/Crank fuse.

dforthof - I'm interested in seeing if I can isolate the problem to the PWM box. When you say to disconnect it, are you suggesting that I cut the wires to it and then connect them without the PWM box attached?

Thanks for your help everyone. I REALLY want to drive this car this summer!!

Jim

[armydoc]

28912

I just wanted to be clear that this is the PWM box in my hand right?

[dforthof]

Hey Armydoc, Yes, that's the PWM box in your hand. There are basiclly four wires going into it, two for the rheostat (the dimmer), one power and one ground. I'm not sure what circuit you used to power the box, so maybe you can do what I'm asking by just pulling the "Courtesy" or "Radio IGN fuse," but I basiclly want you to disconnect the power and ground going to this box and try starting the vehicle then. Note that when disconnected, the gauge lights wont work (obviously). Tell me how it goes!

[armydoc]

dforthof - Thanks again for the reply. I tried removing the fuses but that didn't do anything. I even went so far as to cut the wires going to the PWM box and still nothing. I have a couple questions:

1. Should I just solder the PWM box wires back or since I have it off should I just see if I can get a new one and reattach it?
2. Is it possible that the ignition core itself could have anything wrong with it or is that just simply a mechanical connection aligning the circuits when I turn the key?

I'm truly an amateur when it comes to wiring so I really appreciate your patience and advice.

Jim

[dforthof]

Hey Armydoc, The way I see it, there are two problems we’re trying to fix 1). Engine keeps running after IGN switch is turned off and 2). Gauge lights don’t work. Please inform me if this is incorrect or there are more issues as more issues = more clues as to what is wrong. also, I'm assuming you already disconnected the LED's that caused the problem in the first place to get them out of the mix.
In response to your questions:
1). I was looking at my ride over the weekend and realized I gave you some poor info. There are actually six wires going to the PWM box, make sure the ones you disconnected are the power feed wires, the ones that didn't have an end on them origionally. If you already did this, you can test the box to see if it’s bad by bypassing it - connect the power-feed wires going into the box to the power-output wires coming out of the box, connect white stripe to white stripe and black to black. Basiclly, if you do this, the lights in the gauges should work at their highest brightness when powered (assuming the circuit you wired the box into is powered – you might have to turn the headlamps on??).
2. The most likely reason your engine continues to run after the key is cycled off is because the Blunt-Lead 1 (Red/Light Green Wire) that comes out of the Coyote Harness is remaining powered – this is the signal to the ECM to “run” the engine. If you wired this according to the Coyote fitment manual, than you have this wire hooked up to the orange “EFI or COIL” wire coming out of the FFR fuse block. This circuit should only have power when the Ignition switch is in ON or Start. You can easily test to see if it has power all the time by hooking your test light up to ground and testing to see if the EFI fuse in the FFR block has power when the ignition is off – if this is the case, then yes, a faulty ignition switch might be the culprit, although I would be surprised because the IGN switch can handle a very high load, I would lean more toward a back-feeding circuit somewhere else. Do this test and I tell me what you find.
3. Another idea, completely independent of the two above, is the headlight switch. This gets power from the same circuit as the courtesy lights (CL) wire, so shorting the CL circuit out could potentially fry the headlamp switch. According to the RF schematics, you should be able to completely disconnect the headlamp switch and the vehicle should still start, run and stop normally (but obviously no lights will work). Give this a try.

[armydoc]

dforthof: Thanks again for the advice. Sorry it took me so long to try your suggestions but I work a lot and have a wife and 3 kids...here's where I'm at so far.

1. I completely bypassed the PWM box by cutting the 6 wires and attaching white/white and black/black power-feed. No lights came on my gauges and the car still starts, runs and will not shut off. The test light shows that the EFI fuse is still being powered even with the keys out of the ignition.

2. I disconnected the negative battery cable (I actually had to replace my battery because the constant draw somewhere killed it, a new Optima. The dealer gave me a loaner battery while they try to recharge mine). I reconnected the battery and when I do, there is no draw to the EFI fuse. But...once I start the car and turn it off (the only way I can turn it off is by engaging the interia switch) there is still power going to the EFI fuse.

3. I completely disconnected the headlight switch to see if that was the problem. No change at all. The car still starts, runs and will not shut off with power going to the EFI fuse after being "off".

4. I purchased a generic ignition switch and tried it. Again, the car starts, runs and will not shut off.

So, in summary. I think that the ignition switch is fine since there is no difference in the Factory Five supplied switch and the one I purchased. I am now going to get the wiring diagram/manual out and start from the beginning and carefully follow each wire to see if I possibly mis-wired something or if there is a bad ground or if some of the wire coating has exposed a wire. I am truly at a loss. Any other ideas?

[chopthebass]

Might be worth taking to an auto-electrician who can do a diagnostic on it. I can't believe such a simple mod has caused so much aggro.

[dforthof]

Hey Army, I was on vacation, but just got back...
For the engine shut-off issue:
First, I assure you I am completely qualified to assist you.
The EFI fuse issue is the root of your problem. It should only have power on it when the ignition is in the "on" or "start" position. This fuse powers the “Orange EFI or Coil” wire that you should have spliced into the Blunt-Lead 1 (Red/Light Green Wire) from the Coyote harness. This circuit tells the Coyote computer to keep the engine running (when powered). Since you've confirmed the ignition switch is not the issue, we have to assume that the power is being back-fed onto the circuit from another source when you turn the ignition off… unfortunately; the most likely culprit is the coyote computer or possibly the PCM relay (I hope). To confirm my suspicion, do the following:
1). Get the EFI fuse into a state where there is power on it with the ignition and engine off.
2). Disconnect the Orange Ignition feed wire from the ignition switch and check again to make sure the power is still on the EFI fuse. Obviously, be careful when you do this because there are plenty of hot circuits around the ignition switch and you don’t want to short anything. If the power is gone, stop here and report findings.
3). Remove the “Fuel Pump,” “Choke” and “Turn Signal” fuses one at a time, making sure that the power remains on the EFI fuse in-between all of them, if any of these fuses makes the power come off the EFI fuse, stop here and report findings. If there is still power on the EFI fuse, leave all the fuses out and continue onto the next step.
4). Confirm that the power is coming from the Blunt-Lead 1 (Red/Light Green Wire) by removing the splice you made to the ORG Coil wire and checking the blunt end, if there is still power, switch the two relays (the purple cubes) in the Coyote fuse block and check it again. By “switch” I mean, swap their installation locations.
5). If there is still power with the relays switched, remove them both and tell me which relay pins have power and which ones don’t.
For the Gauge lights issue:
I’m concerned that the LEDs in your gauges are damaged. If you power the black and white wires coming out of you gauges (white=12V+, Black=12V- ground), then the lights should come on, if not, then they are no good. Try just pulling one gauge out and hooking it up directly to your battery.

[armydoc]

dforthof - Again, thanks for taking the time to help me with my situation. I read your response and it makes me eager to get out in the garage and try those things. Unfortunately (or more likely, fortunately) the car was so close to being finished when that happened that I brought it down to Whitby Motorcars in North Carolina to have them do the bodywork/paint and see if they could fix the electronic problem as well. I hope that they will be able to, nevertheless, I wanted to give you a heartfelt thanks for taking the time to offer me help with this situation. People like you are the reason that this community is awesome.

[dforthof]

No problem at all Army, I hope they can fix it, if not let me know.

[Benji]

...

[dforthof]

Hmmm,
That's strange Benji, mine come on full-blast when I bypass the PWM box (just feed 12V directly to the gauge LED lead)...

[Benji]

I'm sorry, I'm talking utter rubbish :(

You are indeed correct and full-blast is indeed the key here, what I meant was, you can't dim LED's the conventional way, the PWM box is needed to dim the lights.