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Discussion Starter #1
I recently purchased a '94 GT for a parts car. It needed a ball joint that had completely torn away from the LCA and caused some fender damage. After getting the car home, I replaced the ball joint and took it for a drive. It drove so nice that I decided to make the necessary repairs and give it to my daughter for her first car.

Full disclosure, this car has had a nitrous system on it and the electric fan has been wired to run via a switch in the interior. There are random wires under the hood that have obviously been tampered with and/or cut. Both battery cables have had new ends installed and they are half-ass at best.

After driving it for a few weeks without issue, now it will not crank. There is an audible click at the starter solenoid (on the starter). Here is a list of things that I have done trying to diagnose the issue:
  1. Tried two different batteries, and had them both tested
  2. Cleaned the battery connections, reassembled using dielectric grease.
  3. Removed, cleaned, greased block ground on timing cover
  4. Removed starter and had tested. Worked perfect.
  5. Checked voltage at starter. Have 12V on main power cable and 13.5V on solenoid wire when key is in start position. This was done with a multimeter using the transmission case for ground, which tells me the ground is good as well. Wiring seems to act as it should.
  6. Cleaned mounting surfaces of starter and block to ensure good ground.
  7. Have not tested neutral safety switch (automatic car), but seems to work as it should. Solenoid clicks when in PARK or NEUTRAL, does nothing when in any other gear.
  8. Checked all fuses under the hood.
  9. Cleaned positive cable running from battery to underhood fuse panel.
  10. Swapped starter relay with horn relay.
  11. Used jumper wire to bypass starter relay. Same clicking noise heard, no crank. Looking at various wiring schematics, this should bypass the ignition and neutral safety switches taking them out of the equation.
  12. I cannot jump the solenoid at the starter due to interference from the k-member and headers.
  13. Turned the engine over manually to rule out the engine being locked-up or the flex plate being in a bad spot.
  14. Run jumper cable from battery ground to starter housing.
Anyone have any ideas? I am not sure if there is any type of alarm system on the car, but I don't think so. I am pretty mechanically and electrically inclined, but am frustrated. There has been some creative wiring done on the car in it's lifetime, but it seems to be working correctly at the starter. I would appreciate any help.
 

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#5

How does that tel you you have a good ground?

Remove the battery negative cable, then take your ground lead and place it on the battery neg post

You will get the same result, with NO GROUND.

Meter tells you a potential, thats it

Do you have the wiring diagram for the start circuit for your car?
 

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Discussion Starter #3
#5

How does that tel you you have a good ground?

Remove the battery negative cable, then take your ground lead and place it on the battery neg post

You will get the same result, with NO GROUND.

Meter tells you a potential, thats it

Do you have the wiring diagram for the start circuit for your car?
Thanks for chiming in, Indy. I was hoping you would. In my mind, if it was not reading voltage at the starter using the trans case as a ground, it could be the power circuit or the ground that is bad. Since it read, I assumed I have both. Like you said, if I had tested using the battery terminal as ground, I could get a false outcome (voltage, but no ground at the starter).
I do have a schematic. Should I be focusing on grounds?
Thanks for the help!
 

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Sounds like a bad connection/ bad cable issue.

Especially since you mentioned their condition, I would suspect them first.

The audible click tells you everything else in the starting circuit is working correctly, or you wouldn’t get the click.
The starter has been tested and verified good.
The only thing in between is the cables and connections. This is a classic symptom of a bad cable/connection.
 

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Discussion Starter #7
Sounds like a bad connection/ bad cable issue.

Especially since you mentioned their condition, I would suspect them first.

The audible click tells you everything else in the starting circuit is working correctly, or you wouldn’t get the click.
The starter has been tested and verified good.
The only thing in between is the cables and connections. This is a classic symptom of a bad cable/connection.
I agree. Other than actually removing the ends that connect to the battery from the cables, I have removed and cleaned them all. Here is a picture of the positive battery terminal before. The black (red is negative duh) wire is 12 gauge residential wire that goes to a switch on the dash that controls the fan...sigh.

Indy, I have attached the schematic I have been using. Tell me more about this voltage drop test.
 

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one lead to batt pos

the other lead to start motor solenoid wht/pk wire

reading at key off, then reading with key in crank

what are they?
 

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Discussion Starter #9
one lead to batt pos

the other lead to start motor solenoid wht/pk wire

reading at key off, then reading with key in crank

what are they?
I'll test it after work. Since I am positive to positive, I assume i am testing something other than voltage. What mode should I have the multimeter in?
 

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dc voltage

why would you assume we would be testing anything other than voltage during a voltage drop test?
 

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Discussion Starter #11
dc voltage

why would you assume we would be testing anything other than voltage during a voltage drop test?
With both leads going to positive, I typically wouldn't expect a reading with the multimeter set to DC. Anyway, I will test what you want and report back.
 

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they are NOT both positive points


look at the wiring diagram, you need to see that, to understand what is going on

hint, one wire with a break in it, is not one wire any more

do you fully understand ?
 

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Discussion Starter #13
they are NOT both positive points


look at the wiring diagram, you need to see that, to understand what is going on

hint, one wire with a break in it, is not one wire any more

do you fully understand ?
I have 9-10V when the key is off. It goes to zero when you turn the ignition to START.

It looks to me like the ignition switch feeds power to W/PK wire. If it makes it through the neutral safety switch, clutch switch, and alarm, it sends power to post 86 on the starter relay. The relay would then transfer power to post 87, which sends it to the starter.

The headlights do not dim when the ignition is in the START position.
 

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so you just tested that indeed the signal from the ignition switch is making it to the solenoid coil

the 9-10volts is saying what before you turn the key to crank?

is that the true voltage at the battery?
 

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Discussion Starter #15
so you just tested that indeed the signal from the ignition switch is making it to the solenoid coil

the 9-10volts is saying what before you turn the key to crank?

is that the true voltage at the battery?
True voltage at the battery is 12.7V. I guess that it is saying I have around a 3V drop between the battery and the solenoid.

It goes zero because it basically has continuity when in the START position?
 

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yes there is continuity.......but more correct is there is NO voltage drop.......

now, here is an issue,,,,,,

you have 12.7volts at battery, yet only 9-10volts dropping from the batt to that wire


we would expect to see near the same battery voltage

IMPORTANT..........are you 100% sure you have 12.7 volt drop at the battery, and 9-10volt drop on that circuit??

i am finding that hard to believe, please verify
 

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Discussion Starter #18
you are measuring at the solenoid, and NOT the relay, right?
That is correct. I am confident in the battery reading, 12.7V. The voltage from the battery positive to the W/PK wire (at the solenoid) was a little tough to tell as it seemed to bounce around. It did seem to settle down a little between 9 and 10V. I am confident the W/PK wire drops to zero when in the START position.
 

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Discussion Starter #20
move your probe from the w/pk, to the heavy red wire on the solenoid repeat test

what do you get?
I finally got around to doing a little more work on the car. I repeated the test on the heavy ready wire and got battery voltage, which is impossible. At that point, I checked for continuity and did not get it. So obviously the heavy red wire is the issue.

Both battery cables are cobbled up at the terminals with bolt-on crimp ends. I took the positive apart, cleaned it well, and then reassembled. Now the starting system works as it should. I had previously only cleaned the crimp-to-battery connections.

Unfortunately, the positive battery cables for '94-95 5.0 cars are no longer available for purchase so I will not be able to repair it the way I would like.

Thanks again Indy for your help!
 
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