starter question
Race Director
Joined: Oct 2002
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From: Gone
CI 6-7-8-9-10 Veteran
St. Jude Donor '03
I would guess the ohm value of the solenoid coil isn't all that much, and measuring between the solenoid terminal and ground, you would be reading the coil resistance, and if low enough, may show as continuity on a simple tester.
Seeing continuity to the positive side, no...you shouldn't. One thing that could cause it would be the theft deterrent relay stuck or shorted.
If you are at the starter right now, remove purple wire, and check if your continuity to + is coming from the wire, or the solenoid post.
That purple wire is what initiates the starting process. Apply +12v to that wire, and your starter should spin.
Seeing continuity to the positive side, no...you shouldn't. One thing that could cause it would be the theft deterrent relay stuck or shorted.
If you are at the starter right now, remove purple wire, and check if your continuity to + is coming from the wire, or the solenoid post.
That purple wire is what initiates the starting process. Apply +12v to that wire, and your starter should spin.
Thread Starter
Instructor
Joined: Aug 2006
Posts: 205
Likes: 0
From: TEXAS
I would guess the ohm value of the solenoid coil isn't all that much, and measuring between the solenoid terminal and ground, you would be reading the coil resistance, and if low enough, may show as continuity on a simple tester.
Seeing continuity to the positive side, no...you shouldn't. One thing that could cause it would be the theft deterrent relay stuck or shorted.
If you are at the starter right now, remove purple wire, and check if your continuity to + is coming from the wire, or the solenoid post.
That purple wire is what initiates the starting process. Apply +12v to that wire, and your starter should spin.
Seeing continuity to the positive side, no...you shouldn't. One thing that could cause it would be the theft deterrent relay stuck or shorted.
If you are at the starter right now, remove purple wire, and check if your continuity to + is coming from the wire, or the solenoid post.
That purple wire is what initiates the starting process. Apply +12v to that wire, and your starter should spin.
Race Director
Joined: Oct 2002
Posts: 16,477
Likes: 26
From: Gone
CI 6-7-8-9-10 Veteran
St. Jude Donor '03
This relay is located right above the BCM in the pass. side footwell. It has 4 wires attached to it:
Coil side:
Yellow - +12v from ignition switch during starting.
Yellow/black stripe - Ground signal supplied by BCM.
Note this will only show continuity to ground during starting (assuming no theft protection is occuring...the BCM has the ability to prevent starting by not supplying this ground signal).
Load side:
Red - +12v from battery
Purple - +12v to starter solenoid during starting.
Full starter system schematic:
Coil side:
Yellow - +12v from ignition switch during starting.
Yellow/black stripe - Ground signal supplied by BCM.
Note this will only show continuity to ground during starting (assuming no theft protection is occuring...the BCM has the ability to prevent starting by not supplying this ground signal).
Load side:
Red - +12v from battery
Purple - +12v to starter solenoid during starting.
Full starter system schematic:
Thread Starter
Instructor
Joined: Aug 2006
Posts: 205
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From: TEXAS
awesome! i've been looking for that schematic! do you happen to have the fullsize pic or a version where the words are more legible 
here's a video of my problem.
http://www.livevideo.com/video/C4252...ont-start.aspx
i didnt get a chance to check the yellow wires, but i did get to check the red and purple... with the purple wire disconnected from the starter, i checked it's voltage when attempting to start the car. it got 14v. i hooked it back up to the starter, attempted to start again and got 5v?? i also want to check the voltage on the red wire when the purple wire is connected to the starter as well, but i didnt get a chance to today.
here's a video of my problem.
http://www.livevideo.com/video/C4252...ont-start.aspx
i didnt get a chance to check the yellow wires, but i did get to check the red and purple... with the purple wire disconnected from the starter, i checked it's voltage when attempting to start the car. it got 14v. i hooked it back up to the starter, attempted to start again and got 5v?? i also want to check the voltage on the red wire when the purple wire is connected to the starter as well, but i didnt get a chance to today.
Last edited by The Viking; Apr 25, 2007 at 07:37 PM.
Race Director
Joined: Oct 2002
Posts: 16,477
Likes: 26
From: Gone
CI 6-7-8-9-10 Veteran
St. Jude Donor '03
If you're getting 12v or more on the purple wire during an attempted start, everything before that is doing what it should, you need not test the yellow wires, they are doing their job, as is the ignition and clutch, etc.
However, evident by the video, your car is experiencing a huge voltage drop when you try to start. If the voltage at the purple wire is dropping that much, either your battery is shot (have you had it load-tested?), or you have a very bad connection between battery and the purple wire...and the theft deterrant relay would be the likely suspect for such a poor connection. especially if you've ever had water intrusion in the pass floor area.
Pull that relay out and closely inspect it. It is like $35 at a dealer. If you have any doubt about it's integrity, replace it. A marginal connection can show good voltage static, but once under load, will fail.
Testing the red wire at that relay during an attempted start will quickly tell you if it's poor relay contact. Low voltage on purple, but still reading high voltage on red wire, would definitely point to bad relay contacts.
If you see that much of a voltage drop on the red wire too, check the 60a start fuse in the footwell fusebox, and if that looks normal and fits tight in it's socket. I have nothing else to suspect other than the battery.
The starter itself could be to blame, but since it does seem to begin to spin normally before dropping out, I tend to doubt it.
However, evident by the video, your car is experiencing a huge voltage drop when you try to start. If the voltage at the purple wire is dropping that much, either your battery is shot (have you had it load-tested?), or you have a very bad connection between battery and the purple wire...and the theft deterrant relay would be the likely suspect for such a poor connection. especially if you've ever had water intrusion in the pass floor area.
Pull that relay out and closely inspect it. It is like $35 at a dealer. If you have any doubt about it's integrity, replace it. A marginal connection can show good voltage static, but once under load, will fail.
Testing the red wire at that relay during an attempted start will quickly tell you if it's poor relay contact. Low voltage on purple, but still reading high voltage on red wire, would definitely point to bad relay contacts.
If you see that much of a voltage drop on the red wire too, check the 60a start fuse in the footwell fusebox, and if that looks normal and fits tight in it's socket. I have nothing else to suspect other than the battery.
The starter itself could be to blame, but since it does seem to begin to spin normally before dropping out, I tend to doubt it.
Last edited by Y2Kvert4me; Apr 25, 2007 at 07:48 PM.
Thread Starter
Instructor
Joined: Aug 2006
Posts: 205
Likes: 0
From: TEXAS
If you're getting 12v or more on the purple wire during an attempted start, everything before that is doing what it should, you need not test the yellow wires, they are doing their job, as is the ignition and clutch, etc.
However, evident by the video, your car is experiencing a huge voltage drop when you try to start. If the voltage at the purple wire is dropping that much, either your battery is shot (have you had it load-tested?), or you have a very bad connection between battery and the purple wire...and the theft deterrant relay would be the likely suspect for such a poor connection. especially if you've ever had water intrusion in the pass floor area.
Pull that relay out and closely inspect it. It is like $35 at a dealer. If you have any doubt about it's integrity, replace it. A marginal connection can show good voltage static, but once under load, will fail.
Testing the red wire at that relay during an attempted start will quickly tell you if it's poor relay contact. Low voltage on purple, but still reading high voltage on red wire, would definitely point to bad relay contacts.
If you see that much of a voltage drop on the red wire too, check the 60a start fuse in the footwell fusebox, and if that looks normal and fits tight in it's socket. I have nothing else to suspect other than the battery.
The starter itself could be to blame, but since it does seem to begin to spin normally before dropping out, I tend to doubt it.
However, evident by the video, your car is experiencing a huge voltage drop when you try to start. If the voltage at the purple wire is dropping that much, either your battery is shot (have you had it load-tested?), or you have a very bad connection between battery and the purple wire...and the theft deterrant relay would be the likely suspect for such a poor connection. especially if you've ever had water intrusion in the pass floor area.
Pull that relay out and closely inspect it. It is like $35 at a dealer. If you have any doubt about it's integrity, replace it. A marginal connection can show good voltage static, but once under load, will fail.
Testing the red wire at that relay during an attempted start will quickly tell you if it's poor relay contact. Low voltage on purple, but still reading high voltage on red wire, would definitely point to bad relay contacts.
If you see that much of a voltage drop on the red wire too, check the 60a start fuse in the footwell fusebox, and if that looks normal and fits tight in it's socket. I have nothing else to suspect other than the battery.
The starter itself could be to blame, but since it does seem to begin to spin normally before dropping out, I tend to doubt it.
Thread Starter
Instructor
Joined: Aug 2006
Posts: 205
Likes: 0
From: TEXAS
i checked the red wire going into the relay, and it had constant 12v+ with and without the purple wire disconnected from the starter. so i went to the dealership and they dont have the old starter relay anymore? here are the pics of the old relay (gray) and the new one (black). the old relay had 4 posts and the new relay has 5. the only difference is the center post. they said i needed to get this 5 wire harness for it, but where does the extra wire go, or do i even need the harness? can i just break off the extra post?
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Race Director
Joined: Oct 2002
Posts: 16,477
Likes: 26
From: Gone
CI 6-7-8-9-10 Veteran
St. Jude Donor '03
From those pics, I think you can just cut off the middle tab, and reuse your existing connector.
Before doing so, on the new relay, make sure you have continuity ( 0 ohms) between post 30, and the middle tab (which should be 87a)...that would be an unused normally closed contact.
If the extra middle post is NOT 87a, then no, you can't cut that post off.
Before doing so, on the new relay, make sure you have continuity ( 0 ohms) between post 30, and the middle tab (which should be 87a)...that would be an unused normally closed contact.
If the extra middle post is NOT 87a, then no, you can't cut that post off.
Thread Starter
Instructor
Joined: Aug 2006
Posts: 205
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From: TEXAS
alrighty. i think i might have found the problem. there is ground harness under the battery tray... i checked the incoming ground and all of the out going grounds to that harness for continuity and it had nothing. doesnt the pcm ground into there? that would probably explain when i pull pcm fuse 23 out the motor and starter spin without any hesitation wouldnt it?