C5 Starting Blues
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Intermediate
Joined: Mar 2004
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From: King George Va
C5 Starting Blues
Need diagnostic help, please.
Drove car recently in humid---not wet---conditions last week. Noticed AC condensate dripping from under the Passenger Side dash.
Later that day, starter did not want to engage. But I found that the starter would engage, and the engine would fire up if I held the key on for 5-8 seconds.
I have checked the battery (it is new, and charged --Optima Red Top), and the cable posts on the battery are clean and tight.
I have not checked the starter connection itself, since it will require jacking the car.
The question I have is this::: Do you think the leaking AC condensate is related? Did it cause problems with a fuze or relay? Or do you think I just have a loose starter cable?
Oh, When I try to start the car (with headlights on--just to provide a severe test), I noticed that the underhood light and the glove box light go out when the key is held on, but the headlights stay on. The other electronics seem to function----but the starter is quiet---not even a clicking sound.
Any ideas---any help appreciated.
Thanks,
Jesse East
Drove car recently in humid---not wet---conditions last week. Noticed AC condensate dripping from under the Passenger Side dash.
Later that day, starter did not want to engage. But I found that the starter would engage, and the engine would fire up if I held the key on for 5-8 seconds.
I have checked the battery (it is new, and charged --Optima Red Top), and the cable posts on the battery are clean and tight.
I have not checked the starter connection itself, since it will require jacking the car.
The question I have is this::: Do you think the leaking AC condensate is related? Did it cause problems with a fuze or relay? Or do you think I just have a loose starter cable?
Oh, When I try to start the car (with headlights on--just to provide a severe test), I noticed that the underhood light and the glove box light go out when the key is held on, but the headlights stay on. The other electronics seem to function----but the starter is quiet---not even a clicking sound.
Any ideas---any help appreciated.
Thanks,
Jesse East
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
Dude,,,Ive been there and done this one!!!You need to disconnect your battery, remove the BCM and set it in nice warm place for a few hours. Then you need to look directly above the area where the BCM was removed (near the fire wall) and you will find a couple of relays
One is the Theft Control Relay and the leak could have gotten water in it. This happened to my 98 Coupe. The relay was FULL of water and the contacts were rusted off. I have to go out to a Prince concert. If you need me to give you the color code for the wires so that you can figure out which one is the Theft Control relay, please let me know. When I get back I will crack open the shop manual. I believe that there are two large purple wires that carry the starter solonid current on the plug. Dont quote me on that. I hot wired the circuit to start the car until I could get a new relay.
BC
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Joined: Mar 2004
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From: King George Va
Thanks, Bill.
Can you tell me where and how to recognize the BCM? Do I have to remove a panel inside the car?
Also, the wire colors to bypass the Theft Relay would be helpful.
Jesse East
Can you tell me where and how to recognize the BCM? Do I have to remove a panel inside the car?
Also, the wire colors to bypass the Theft Relay would be helpful.
Jesse East
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
The BCM is the LARGE silver box next to the fuse box in the passengers foot well. It can be accesed behind the toe board. Once you remove the toe board you will see the BCM, fuse box and some wiring connectors to the left of the BCM. The wiring connectors are part of the serial buss that all of the modules communicate with each other on.The Theft deterrent relay (as per my 98 service Manual) should have the following four color wires to support the following circuits:
1. RED = 12 Volts DC from MAXI fuse (STARTER) 60 amp
2. Purple = to Starter solonid
3. Yellow/black stripe = From BCM. Ground for coil of the relay. BCM turns on this function when it sees that the proper functions have been met for proper ID.
4. Yellow = from IGN-2 MAXI fuse 60amp, thru ignition switch, instrument panel fuse# 14 10amp (CRK), clutch pedel position or switch/Park nuteral switch
BC
1. RED = 12 Volts DC from MAXI fuse (STARTER) 60 amp
2. Purple = to Starter solonid
3. Yellow/black stripe = From BCM. Ground for coil of the relay. BCM turns on this function when it sees that the proper functions have been met for proper ID.
4. Yellow = from IGN-2 MAXI fuse 60amp, thru ignition switch, instrument panel fuse# 14 10amp (CRK), clutch pedel position or switch/Park nuteral switch
BC
Last edited by Bill Curlee; Jul 18, 2004 at 09:45 PM.
Thread Starter
Intermediate
Joined: Mar 2004
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From: King George Va
Bill,
BCM located, extracted, and dried out. Theft Module found but cant see how to remove, so I dont know how degraded it is. There was still a lot of moisture in all of the foam insulation under there. Its been drying out (car door left open in garage) for several days now.
Is there an AC condensate drain that may be stopped up?
Can you help with directions on how to remove the TC Module---dont want to break something.
Thanks,
Jesse East
BCM located, extracted, and dried out. Theft Module found but cant see how to remove, so I dont know how degraded it is. There was still a lot of moisture in all of the foam insulation under there. Its been drying out (car door left open in garage) for several days now.
Is there an AC condensate drain that may be stopped up?
Can you help with directions on how to remove the TC Module---dont want to break something.
Thanks,
Jesse East
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
The THEFT CONTROL relay is a small black plastic cube about 2" X 2" square. It should be easy to remove and the wiring plug should unplug after you push in on the small latch that prevents it from coming loose on it's own. It is attached to the fire wall with a small clip. Get a mirror, find the wires that I described and see if you can figure out how the relay detaches.
As for the drain. It can be accessed from the top of the engine but it is a real PITA!
It's very difficult to locate from the top. Your best bet is to jack up the passengers side, ""JACK STANDS PLEASE"", crawl under the car, find the fire wall area, look up directly aft of the back side of the passengers cylinder head. You should see a 2" long black "L" shaped rubber hose that is sticking off the fire wall. Pull it off (water may gush out!!), snip off the nipple end so it is open. Make sure that the metal fitting that it came off of is not plugged up with slime. If the tube is clear slide the hose back on all the way to the fire wall. Some people use a very small dab of silicone sealer to make sure that it stays on the metal fitting. That problem is now solved.
Feel free to ask more questions.
Bill C
As for the drain. It can be accessed from the top of the engine but it is a real PITA!
It's very difficult to locate from the top. Your best bet is to jack up the passengers side, ""JACK STANDS PLEASE"", crawl under the car, find the fire wall area, look up directly aft of the back side of the passengers cylinder head. You should see a 2" long black "L" shaped rubber hose that is sticking off the fire wall. Pull it off (water may gush out!!), snip off the nipple end so it is open. Make sure that the metal fitting that it came off of is not plugged up with slime. If the tube is clear slide the hose back on all the way to the fire wall. Some people use a very small dab of silicone sealer to make sure that it stays on the metal fitting. That problem is now solved.Feel free to ask more questions.
Bill C
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Joined: Mar 2004
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From: King George Va
Bill.
I now have TCM out of car. The 4 thin (appears to be aluminum) connecting prongs have a very thin coat of oxidation. No signs of any large moisture problem inside the connector area. I can clean the prongs, and give her a try. However, there could be moisture buildup inside the module. THis is not a commuter car, so I could wait for the part----and it seems like it couldnt be too expensive. Im guessing about $15 or so. Will check tomorrow.
Question: Did you disassemble the module itself----or did you just go ahead and replace it when you found water inside the connector?
Thanks very much for your help. Hopefully I will be able to get this beast back on the road without having to depend on mr gw.
Jesse East
I now have TCM out of car. The 4 thin (appears to be aluminum) connecting prongs have a very thin coat of oxidation. No signs of any large moisture problem inside the connector area. I can clean the prongs, and give her a try. However, there could be moisture buildup inside the module. THis is not a commuter car, so I could wait for the part----and it seems like it couldnt be too expensive. Im guessing about $15 or so. Will check tomorrow.
Question: Did you disassemble the module itself----or did you just go ahead and replace it when you found water inside the connector?
Thanks very much for your help. Hopefully I will be able to get this beast back on the road without having to depend on mr gw.
Jesse East
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Thread Starter
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Joined: Mar 2004
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From: King George Va
Local mr gw wants $31 for the unit, but they have it in stock. Guess I will spring for it so I wont have to do this again soon. Hope this is all I need to bring this baby back to life.
Also, I noticed when I unplugged the BCM that the larger connector had a thin sliver of plastic (sort of like a comb) that was inserted into the side of the connector. There was nothing like this in the other two smaller connectors. Question: Do you think this was just a guide tool to be sure to get proper allignment (and not bend) the prongs in the connector?----or, was this added in a TSB to make sure that there is a good connection in this connector?
Thanks,
Jesse East
Thanks,
Jesse East
Also, I noticed when I unplugged the BCM that the larger connector had a thin sliver of plastic (sort of like a comb) that was inserted into the side of the connector. There was nothing like this in the other two smaller connectors. Question: Do you think this was just a guide tool to be sure to get proper allignment (and not bend) the prongs in the connector?----or, was this added in a TSB to make sure that there is a good connection in this connector?
Thanks,
Jesse East
Thanks,
Jesse East
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Jesse
Did you determine that the relay was bad? I took the cover off mine and saw that it was deterroriated! The cover snaps on and off real easy and it will not hurt the relay to remove it. I recommend making sure that the relay is the problem rather than just replacing it.
You can also jumper the wires to bypass the relay and make the car run until you get a new relay if it craps out prior to getting a new one. If you need the color of the wires to jumper I can provide.
BC
Did you determine that the relay was bad? I took the cover off mine and saw that it was deterroriated! The cover snaps on and off real easy and it will not hurt the relay to remove it. I recommend making sure that the relay is the problem rather than just replacing it.
You can also jumper the wires to bypass the relay and make the car run until you get a new relay if it craps out prior to getting a new one. If you need the color of the wires to jumper I can provide.
BC