No start (via key) Keyless entry and anti-theft??

Labora

Founding Member
Jun 11, 2000
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Dallas, Texas
I am tracking down a no start issue on my 94. (Via the key, when I jump the starter solenoid the car turns over.)

Anyhow I am following this diagram. I've tested everything up to the anti-theft and keyless entry modules. I was wondering where these are located, and any tips on testing them would be helpful.

Currently my testing shows I have power when I turn the key to START, I also took a spare clutch pedal position switch and ziptied it "down" and I have power on both sides of that switch like I should.

Thanks for any help.

(I'm pretty sure the keyless is in the trunk/driver side was hoping someone would confirm, the anti-theft I am clueless on.)
 
If you follow the diagram I started with the switch and am working my way to the starter.

On the ignition switch side I've stopped at the keyless/anti-theft modules. (Everything checks out good before that.) On the opposite side I've checked the fuses and the car is a 5spd.

Which puts me stuck in the middle of whatever modules this car may/not have.
 
As a super quick test, have you checked the slave starter relay in the underhood fusebox? Look for 12V while cranking at terminal 86. If you have it, the issue is after your keyless and alarm.
 
Nope I missed that starter relay, but there it is staring me in the face when I look at my fuse box layout again in the book. /facepalm/

I have a extra relay too, I'll swap it in then check what you suggest if that doesn't solve the problem.
 
Sounds good. Because this is an easy access point, if needed you can temporarily rewire the circuit, bypassing the factory keyless/alarm. That underhood relay makes a nice pick-up point when doing this rewiring (it's a PITA to access the starter solenoid under the car).
Then at least you can drive the car around while figuring out what went sideways in the factory pathways.
 
I have a dealer installed alarm and its also my keyless and its actually installed above the gas pedals in that area, kind of just shoved in.

The NORMAL keyless spot is in the trunk on the left hand side behind the trunk molding (the grey stuff, I can't think of the proper name at this time)

-Dan
 
I thought that box in the trunk was for Keyless entry only. Our cars didn't come with a Factory anti-theft system, correct?

And even the anti theft systems in later Mustangs would still allow you to crank the car, it just wouldn't start.

Remember, when you turn the key to "Start", the ignition switch will send out 2 signals, one for all the starting gear such as fuel, spark, etc.. and the other will signal the starter to turn over. You said you traced circuits back to the keyless entry, well of course it will have power in Run, everything will.

You need to be focused on what gets power when you hold the key in "Start". Might need another set of hands to do that. Figure out all the circuits where the starter relay plugs in and use a test light and have someone try to start the car. That's the first place I'd try.

Again, I don't believe there is any wiring that has to do with starting the car running back to the rear.
 
I thought that box in the trunk was for Keyless entry only. Our cars didn't come with a Factory anti-theft system, correct?

And even the anti theft systems in later Mustangs would still allow you to crank the car, it just wouldn't start.

Remember, when you turn the key to "Start", the ignition switch will send out 2 signals, one for all the starting gear such as fuel, spark, etc.. and the other will signal the starter to turn over. You said you traced circuits back to the keyless entry, well of course it will have power in Run, everything will.

You need to be focused on what gets power when you hold the key in "Start". Might need another set of hands to do that. Figure out all the circuits where the starter relay plugs in and use a test light and have someone try to start the car. That's the first place I'd try.

Again, I don't believe there is any wiring that has to do with starting the car running back to the rear.

I have been testing this in the start position. There is only a certain pin on the start circuit that gets power when the key is in that position. Now weather or not this circuit goes to the back of the car I'm not sure, but per the Ford diagram it does go through both the keyless and anti-theft.

(Weather or not my car has those, and where they are located I'm clueless on.) I'll be checking in the trunk today, hopefully I figure something out. :shrug:
 
That box in your trunk is for the keyless entry, I don't think it has anything to do with antitheft. I've been told a few times that even though our cluster has the "Theft" light in it, it wasn't implemented until the 96 model year. In those cars, the key has to be programed to the car. But even if the key doesn't match, it'll still turn the car over, just won't start. It was called the PATS system. Our cars don't have it.

I just read your build thread, nice job you did! I'm not sure what your problem is going to be though given the fact that alot of wires were moved/hidden. Could be anywhere now. I'd start at the starter and work my way back to the relay, then into the car.
 
Swapped the relay, car still won't start via the key. Can anyone give a clue where the modules are?

Are you using an original Key? I don't know when Ford mustangs got the RFID system. My 97 Probe did not have it. My 2001 Ranger does.

If your car requires a key with a "chip" in it, you do have one we have to assume.

Then there is the inertial fuel pump shut off switch. Have you checked into that?
 
Are you using an original Key? I don't know when Ford mustangs got the RFID system. My 97 Probe did not have it. My 2001 Ranger does.

If your car requires a key with a "chip" in it, you do have one we have to assume.

Then there is the inertial fuel pump shut off switch. Have you checked into that?

did you not read a word in the post above yours? I know you're trying to help, but that has been covered already.

It's amazing how many people don't read all the replies in threads, there's alot of good information to be learned if you just read the material!

Oh, and the inertial switch would do nothing to the starter circuit, all it does is cut the fuel pump off.
 
That box in your trunk is for the keyless entry, I don't think it has anything to do with antitheft. I've been told a few times that even though our cluster has the "Theft" light in it, it wasn't implemented until the 96 model year. In those cars, the key has to be programed to the car. But even if the key doesn't match, it'll still turn the car over, just won't start. It was called the PATS system. Our cars don't have it.

I just read your build thread, nice job you did! I'm not sure what your problem is going to be though given the fact that alot of wires were moved/hidden. Could be anywhere now. I'd start at the starter and work my way back to the relay, then into the car.

I actually didn't have to touch anything to do with the starter/fuse box harness, most of the wires you have to stretch come from the computer harness on the passenger side.

I tore the trunk apart today and found the keyless entry module. (Also put new batteries in the remote today the keyless does work.) Anyhow I was by myself so turning the car to start while hitting the pins with a testlight was out of the question. :notnice:

My car didn't have a anti-theft module in the stock location, but it does have the wires for it. (The next page on my Ford book shows the pin outs and colors for it, the wires for it are actually right next to the keyless.) I'm guessing it was a dealer installed extra.

Are you using an original Key? I don't know when Ford mustangs got the RFID system. My 97 Probe did not have it. My 2001 Ranger does.

If your car requires a key with a "chip" in it, you do have one we have to assume.

Then there is the inertial fuel pump shut off switch. Have you checked into that?
PATs didn't start until 96 so there is no chip in 94/95s. The Fuel pump cutoff is for just that, nothing to do with the starter. ;)

I followed HISSIN50's advice and made a jump wire from pinout 85 (which is on in start only) and pinout 87 (starter solenoid) and was able to use the key that way. But that doesn't exactly give me a clue what the issue is. :shrug: (And before someone says the starter relay in the fuse box I tried 4 different ones, so it isn't likely.)

Look for 12V while cranking at terminal 86. If you have it, the issue is after your keyless and alarm.
No power to 86 while in start.

Call me stumped, until I can get a second hand to help me test the wires in the trunk.
 
I might have simply had the numbers backwards on the relay. Amongst 85 and 86, one is ground and one will show 12V while cranking. I had checked it once on mine and thought 86 was what showed 12V while cranking but I could be entirely wrong.

In any case, you have cranking 12V going into that relay. That's good. As you noted and thoroughly tested, that would have suggested the relay is bad. Did all the relay receptacle terminals look good? Sometimes they get loose or recede into the fusebox.

So right now, you can jump 85 to 87 and it starts, no? In other words, the pathways for 85 and 87 are functioning properly (I surmise).

The one remaining item to check: Make sure terminal 30 on the starter relay has battery power. This could be why you can jump 86 to 87 (and use the cranking wire to power the solenoid) but the relay exciting doesn't power the solenoid (because 30 has no battery power to provide).
Also make sure the other coil terminal (apparently 86 for you) shows continuity to ground.


If that doesn't help or you think you'll be running with the jumper wire for a bit, I'd rig up a quick relay (so you don't overburden the cranking wire [that goes to your terminal 86]). Just wire it up in parallel with your existing relay.

Good luck.
 
Well it's too bad you have to live way the heck over in Texas or I'd come give you a hand. These problems are fun to tackle sometimes!

And yes, that's what's puzzling me about the relay too. You should have a heavy 12 volt circuit (for starter), a circuit going to the starter, a ground and one more coming from the ignition switch. It's a really simple circuit I would think. I'll go out later on and test on a working system and report my findings as to what the relay terminals behavior is supposed to be.
 
After sleeping on this, I got to thinking about my ever shrinking list of things to do. One of which was to get the headlights working. (I ran over one of the connectors effectively shattering it into a million pieces.) Well of course while I was pondering this I got to thinking about the grounds for the lights, which since it was further down my list then the starter I had not yet fastened them to the body.

After testing them with a pair of jumper cables, the car started right up via the key. :nice:

So needless to say I should feel like a bit of a fool. But I am just happy it turned out to be something simple, and nothing can kill my good vibes from finally getting to drive the car today. :D

Thanks for all the help. :SNSign:
 
It's always the "simple" things, isn't it? I had problems with my driver's airbag sensor and my left headlight not working (along with a few other items) when I did my Cobra conversion. Turned out I had forgotten to plug in a connector behind the driver's wheel well. Plugged that in and the small laundry list of non-working items cleared up.

Did you find a replacement for the connector you smashed? I'm sure the StangNet crew here has a resource somewhere to help.
 
It's always the "simple" things, isn't it? I had problems with my driver's airbag sensor and my left headlight not working (along with a few other items) when I did my Cobra conversion. Turned out I had forgotten to plug in a connector behind the driver's wheel well. Plugged that in and the small laundry list of non-working items cleared up.

Did you find a replacement for the connector you smashed? I'm sure the StangNet crew here has a resource somewhere to help.

You can buy the new headlight sockets at just about any parts store, I went ahead and replaced both. Broke the driverside one, and had to extend the passenger side (part of hiding the wires) so might as well replace it with a new clip that isn't old/brittle.

Speaking of airbag lights, that is the only one that is currently flashing, I'm hoping grounding everything like it should will clear it up. Pretty sure it will.
 
You can buy the new headlight sockets at just about any parts store, I went ahead and replaced both. Broke the driverside one, and had to extend the passenger side (part of hiding the wires) so might as well replace it with a new clip that isn't old/brittle.

Speaking of airbag lights, that is the only one that is currently flashing, I'm hoping grounding everything like it should will clear it up. Pretty sure it will.

count the flashes... sometimes the bag light will flash if the battery was left disconnected for a long time.