starting and brake light issues..

[Brett87lx]

Well, after putting the mustang to bed for the year I pulled out my trusty 89 SHO complete with brand new CPS, water pump, and timing belt. So far the car is doing pretty good considering this is the first time I have really started to rely on the car for a daily winter driver. Anyways, here is what it is doing.

Every now and then on startup I go to start it, and the engine will not turn over. The car still has power, but when I turn the key the engine won't turn. After a couple seconds of holding the key down, or after a couple tries of turning the key on/off the car will fire up as if nothing was wrong. I usually would think its the starter going bad, but it doesn't turn over slowly like I would expect a bad starter to do. It turned over as fast as it always has and fires the car right up.

Secondly, my brake lights don't appear to be coming on while driving. I would watch the refection of the third brake light in the rear window, and it doesn't come on when I push the pedal down, but it will flash on as I am releasing the pedal. I just tried it though while I was parked in my driveway and it is working fine, but I bet as soon as I start driving it will go back as it was before. headbang

Any ideas for me?

Thanks.

<small>[ November 08, 2003, 01:26 AM: Message edited by: Brett87lx ]</small>

 

[SHOPWR]

is it possible that you have a bad connection to your brake light switch? thats what was wrong with my 89 SHO. a wire was hanging down from under the dash and when i applied the brake it pulled the wire out and there for my third break light was not illuminating.

 

[Brett87lx]

SHOPWR:
is it possible that you have a bad connection to your brake light switch? thats what was wrong with my 89 SHO. a wire was hanging down from under the dash and when i applied the brake it pulled the wire out and there for my third break light was not illuminating.

I will check that out. My car is also an 89, and I was thinking something was probably wrong with the brake light switch. I thought I would check here first.

 

[projectSHO89]

As mentioned, the brake light switch is your most likely cause of the problem.

For the "No Crank" problem, cause will likely be one of the following: Ignition switch, clutch interlock switch, or starter relay.

To troubleshoot it, you will need a meter or a 12 VDC test light and some luck.

For the starter relay, check for battery voltage at the small wire of the starter with the clutch pedal depressed and the ignition switch in START. WARNING: Exercise extreme caution while making this check! You can be injured if the starter motor engages during this test! If there is no voltage there, proceed to the next step.

Check at the clutch interrupt switch. One wire (WT/PK) should be hot whenever the ignition switch is in START. If so, check the other wire (R/LB) on the interrupt switch with the pedal depressed and as above. If battery voltage is measured on both terminals of the switch but not on the starter relay S terminal, there is an open circuit between the switch and the starter. If there is no voltage on either wire, the problem is most likely in the ignition switch itself.

Steve

 

[rangerj]

Here's some ideas just for you!

Clean the battery terminals. Then clean the main ground to the engine, and as many other grounds as your 89 has. Check out your model year in the electrical diagrams Bizzy has provided to find the grounds, especially those in the starter and ignition system.

It would also be a good idea to do an amp draw test on the starter. rangerj