Help - Won't Start (not battery)
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Safety Car
Joined: Dec 2001
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From: Indianapolis Indiana
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Help - Won't Start (not battery)
Well, I went out to the car today and it wouldn't start. It has had this 'electrical glitch' non-starting issue intermittently (about 3 times) ever since I loaned it out one evening about a month ago (I trust the guy, so I don't assume foul play). The issue started with the symptoms listed below, but always eventually started after a few tries, and 90% of the time there was no issue at all. Tonight it would not start after dozens of tries.
Symptoms:
- no spark, nor does the starter turn over.
- all electrical seems to turn on fine, the battery is okay, and putting a portable jumper unit on it doesn't help.
- no current codes
- holding the ingition to "start" and letting the clutch in/out causes the relay? in the pass footwell to switch, so I'm pretty certain it has nothing to do with the switch under the clutch pedal.
Symptoms:
- no spark, nor does the starter turn over.
- all electrical seems to turn on fine, the battery is okay, and putting a portable jumper unit on it doesn't help.
- no current codes
- holding the ingition to "start" and letting the clutch in/out causes the relay? in the pass footwell to switch, so I'm pretty certain it has nothing to do with the switch under the clutch pedal.
Race Director
Joined: Oct 2002
Posts: 16,477
Likes: 26
From: Gone
CI 6-7-8-9-10 Veteran
St. Jude Donor '03
Originally Posted by BQuicksilver
- holding the ingition to "start" and letting the clutch in/out causes the relay? in the pass footwell to switch, so I'm pretty certain it has nothing to do with the switch under the clutch pedal.
The relay in the pass footwell you hear clicking is called the theft deterrant relay. This relay (when energized) is what sends 12v to the starter solenoid. It is located right next to the BCM (the silver colored box in the pass. footwell).
The fact you hear it clicking (relay pulling in), not only indicates the clutch pedal switch is working, it also rules out a bad key/ignition switch issue, as the BCM supplies the ground signal to the coil of that relay. If it were a key problem, the BCM wouldn't supply ground to the relay coil, and the relay wouldn't pull in even when power from the clutch switch was applied.
Doubtful, but you could first check the 60a fuse labeled "starter" in the footwell fusebox. If this is good, the next step would be to check the wires at the theft-deterrant relay. It can be identified by the 4 wire colors...red, purple, yellow, yellow/black stripe. The yellow wires are the coil wires, we know they are doing ok if the relay is pulling in when trying to start.
The red wire should +12v at all times. Verify this first.
If that has 12v, the next step would be to have someone depress the clutch, and turn the key to start. Relay will click. Now check the purple wire, at this point it should have +12v. This purple wire runs directly to the starter solenoid. If you have 12v there during an attempted start, and still no response, almost definitely your starter is bad. The only other possibility would be a bad connection or broken/burnt wire at the starter terminals.
I had this happen to me earlier this year, same symptoms. I replaced the starter, and all has been well since.
Last edited by Y2Kvert4me; Dec 15, 2005 at 08:34 PM.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Originally Posted by Y2Kvert4me
This is a big clue, and rules out a lot of possibilities.
The relay in the pass footwell you hear clicking is called the theft deterrant relay. This relay (when energized) is what sends 12v to the starter solenoid. It is located right next to the BCM (the silver colored box in the pass. footwell).
The fact you hear it clicking (relay pulling in), not only indicates the clutch pedal switch is working, it also rules out a bad key/ignition switch issue, as the BCM supplies the ground signal to the coil of that relay. If it were a key problem, the BCM wouldn't supply ground to the relay coil, and the relay wouldn't pull in even when power from the clutch switch was applied.
Doubtful, but you could first check the 60a fuse labeled "starter" in the footwell fusebox. If this is good, the next step would be to check the wires at the theft-deterrant relay. It can be identified by the 4 wire colors...red, purple, yellow, yellow/black stripe. The yellow wires are the coil wires, we know they are doing ok if the relay is pulling in when trying to start.
The red wire should +12v at all times. Verify this first.
If that has 12v, the next step would be to have someone depress the clutch, and turn the key to start. Relay will click. Now check the purple wire, at this point it should have +12v. This purple wire runs directly to the starter solenoid. If you have 12v there during an attempted start, and still no response, almost definitely your starter is bad. The only other possibility would be a bad connection or broken/burnt wire at the starter terminals.
I had this happen to me earlier this year, same symptoms. I replaced the starter, and all has been well since.
The relay in the pass footwell you hear clicking is called the theft deterrant relay. This relay (when energized) is what sends 12v to the starter solenoid. It is located right next to the BCM (the silver colored box in the pass. footwell).
The fact you hear it clicking (relay pulling in), not only indicates the clutch pedal switch is working, it also rules out a bad key/ignition switch issue, as the BCM supplies the ground signal to the coil of that relay. If it were a key problem, the BCM wouldn't supply ground to the relay coil, and the relay wouldn't pull in even when power from the clutch switch was applied.
Doubtful, but you could first check the 60a fuse labeled "starter" in the footwell fusebox. If this is good, the next step would be to check the wires at the theft-deterrant relay. It can be identified by the 4 wire colors...red, purple, yellow, yellow/black stripe. The yellow wires are the coil wires, we know they are doing ok if the relay is pulling in when trying to start.
The red wire should +12v at all times. Verify this first.
If that has 12v, the next step would be to have someone depress the clutch, and turn the key to start. Relay will click. Now check the purple wire, at this point it should have +12v. This purple wire runs directly to the starter solenoid. If you have 12v there during an attempted start, and still no response, almost definitely your starter is bad. The only other possibility would be a bad connection or broken/burnt wire at the starter terminals.
I had this happen to me earlier this year, same symptoms. I replaced the starter, and all has been well since.
EXCELLENT write up!! 
Couldnt have said it better myself! 
BC
Tech Contributor
Joined: May 2003
Posts: 7,035
Likes: 134
From: North Augusta, SC
Check to make sure the battery terminal bolts are both snug (especially the red one). I've seen cars not start because the terminals just didn't have enough contact with the battery to pass the required amps that the starter needs, but everything else on the car works just fine 
Good luck, let us know what you find
Good luck, let us know what you find
2nd Gear
Joined: Dec 2012
Posts: 2
Likes: 0
hi guys, i have the same problem it has done it the 2.5 years i have owned it, but has always started after holding the key to start for 10-45 sec. do you think it is still the starter, just seems like it would have completely failed by now. thanks
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