Code C1243HC BPMV
Thread Starter
Tech Contributor
Joined: Dec 2006
Posts: 10,962
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From: Van Buren Arkansas
Wounded Warrior Escort '11
Code C1243HC BPMV
Ok Gents and Ladies, This is the current code for my '99 Coupe with Active Handling. Ground test shows good and the book states its motor is turning slow. Only happens on startup and if I clear the code, it stays gone till the next morning at cold startup at which time it comes back. Has anyone repaired the BPMV before or know of someone who can? Other options or thoughts?
Safety Car
Joined: Jan 2001
Posts: 4,386
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From: Boise ID
I have not heard of anyone repairing them. I replaced the BPMV on my 2000 last year. Some people have had success by stomping on the breaks repeatedly on wet roads to exercise the pump. This did not help mine. There is also a thread out there which describes how to take the EBCM off and hooking up 12V to pin 8 of the motor and exercise it that way. This also did not work or me as motor was shot and was pulling over 20amps.
Here is a decent link:
http://forums.corvetteforum.com/c5-t...c-c1243-h.html
Here is a decent link:
http://forums.corvetteforum.com/c5-t...c-c1243-h.html
Last edited by 87SAM; Dec 17, 2010 at 04:20 PM.
Thread Starter
Tech Contributor
Joined: Dec 2006
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From: Van Buren Arkansas
Wounded Warrior Escort '11
Very interesting read and Thank You. Hopefully we'll get a little rain shortly and I'll force that pump to run otherwise will have to manually run it with a wire to pin 8
Thread Starter
Tech Contributor
Joined: Dec 2006
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From: Van Buren Arkansas
Wounded Warrior Escort '11
I decided to gain access to it to test, so removed the radiator and behold, I discover the radiator had a hairline crack in it. The BPMV had dried coolant all over it as well from the leak but the connector to the EBTCM was clean and dry. Anyway, ordered a radiator. Hoping to avoid spending for a new BPMV.
Thread Starter
Tech Contributor
Joined: Dec 2006
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From: Van Buren Arkansas
Wounded Warrior Escort '11
This morning, I took the EBTCM off the BPMV and manually applied power to pin 8 as described in the thread from earlier in the year that was referenced to me by "87SAM". The BPMV motor did in fact run although it was a bit sluggish. I ran it several more times and up to as much as 30 seconds. It smoothed out real nice. I'm therefore assuming the brake fluid is needing to be flushed all the way through and I do have a brake pressure bleeder, so I'll be getting to that after the new radiator gets here and installed.
Thread Starter
Tech Contributor
Joined: Dec 2006
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From: Van Buren Arkansas
Wounded Warrior Escort '11
Well, when I discovered the radiator crack and got it pulled out, the EBTCM/BPMV is right there and easily accessible. No sense in waiting around. It would have been a lot harder when everything else was back in. So for now, I'll have to wait for the new radiator.
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Instructor
Joined: Jul 2008
Posts: 145
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From: Macon NC
Been There Done That
If you really want to exercise the BPMV then here are a couple of posts that I made on building an exerciser. I changed the brake fluid using the BPMV motor to pump the fluid through the system. I have not had a fault since I changed the fluid.http://forums.corvetteforum.com/c5-t...xed-again.html
Here is a diagram of my BPMV
http://forums.corvetteforum.com/c5-t...-handling.html
Thread Starter
Tech Contributor
Joined: Dec 2006
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From: Van Buren Arkansas
Wounded Warrior Escort '11
I was going to use a pressure bleeder that I have already but having a way to actuate the pump without removal would be great. I see your pictures but where are you connecting this? Did you come up with a connector for it since it doesn't look like wiring for the serial data buss?
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From: Van Buren Arkansas
Wounded Warrior Escort '11
Yeah, I'm trying. Since I got the car back from my son a couple of months ago now, I've been fixing this and that on it. First was the driver's window regulator wore out. The clutch was already toast when I got it back so its now got a new LS7 clutch in it. Just replaced a weatherstrip and the driver's side havc actuator and now discovered this leaking radiator at the same time I was looking at this code showing up for the BPMV. Also have a TPS transmitter on order right now as well. Oh well, little by little its coming together. As I've said to many people in here, nothing lasts forever and that includes my own cars.
Tech Contributor
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From: Horncastle Lincolnshire, England
2023 C5 of the Year Finalist - Unmodified
Yeah, I'm trying. Since I got the car back from my son a couple of months ago now, I've been fixing this and that on it. First was the driver's window regulator wore out. The clutch was already toast when I got it back so its now got a new LS7 clutch in it. Just replaced a weatherstrip and the driver's side havc actuator and now discovered this leaking radiator at the same time I was looking at this code showing up for the BPMV. Also have a TPS transmitter on order right now as well. Oh well, little by little its coming together. As I've said to many people in here, nothing lasts forever and that includes my own cars.
Thread Starter
Tech Contributor
Joined: Dec 2006
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From: Van Buren Arkansas
Wounded Warrior Escort '11
And a very Merry Christmas to you all as well! Yeah, my car has a ton of miles on it so the interesting part is that I'm experiencing things now or earlier that others will have happen to them later on. Hopefully I'll have the new radiator sometime this week so I can put her together again.
Thread Starter
Tech Contributor
Joined: Dec 2006
Posts: 10,962
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From: Van Buren Arkansas
Wounded Warrior Escort '11
I got the new radiator installed today and fired it up. No more codes from the BPMV so the next on the list will be flushing all the brake fluid from the master cylinder, through the BPMV to each wheel.
