I'm really getting fed up of getting the "Service ABS message" on startup. Comes on now when cold about 1 in 5 times. Since the DTC code is C1243 clearly I have to replace the BPMV. Checked out the grounding issues a while back. Not the problem.

Since these run at over $1000 these days from GM parts direct I was going to look around and see if I could pick up a total unit (BPMV+EBTCM) used, for less. My qustions to the more knowledagable of you out there.
1. If I replace the whole unit, flush the oil lines etc do I still have to bring it to a service shop and have it reprogrammed.
2. what does the reprogramming entail anyway.
3. Will a dealer do it if I replace the unit myself.
4. Finally what goes wrong with these pumps. Seems to be a common problem. Crappy QC, or brushes, or something else.

 

C1243 means your "BPMV motor has stalled"..Although you could replace the BPMV yourself, you have to bleed the ABS system which requires Tech II. For those of you like me that don't have access to Tech II, you've got 2 options. Replace the BPMV yourself and tow the car to a shop with Tech II to have it bled, or just take it in to have the BPMV replaced. The advantage is that you've already done all of the trouble shooting so you won't have to pay the mechanic to diagnose the problem for you. You might want to remove the EBCM yourself and send it to ABS Fixer (Brandon) as it may be involved.
At this point, You've got to additional possibilities. Replace the EBCM or replace both the EBCM and the BPMV. The service manual calls for you to measure the resistance between each pump motor control circuit and the housing of the BPMV, if that checks our okay, you replace the EBCM.. if not you replace them both. Since most people do not have the equipment to do this the best we can do is to replace the EBCM. If that doesn't work, you'll have to go back and replace the BPMV.

The procedure for replacing the EBCM is very simple. The only special tool you need is a T-20 torx screw driver. I have a Craftsman tool set that has a 1/4" drive screwdriver with and adapter for many different size bit. Unfortunately, the adapter was to long to fit between the EBCM and water pump, so I purchased a set of Craftsman 5 pc. torx screwdriver set that worked fine. A flathead screwdriver may also be needed to pry apart the EBCM from the BPMV

1 - make sure the car is off.
2 - you will probably need to remove the airbridge to get to the EBCM.
3 - remove the wire harness by first removing the white plastic clip that locks it in place (I cut it off and replaced it with a zip-tie) , then lift gray handle and pull back on the wire harness. At this point, you will be able to see the second wire connection that is removed by pulling down .
4 - The service manual call for you the remove the 2 insulator nuts that hold the BPMV to the brackets and lift the EBCM/BPMV out of the bracket. I do not think this step is necessary because there is plenty of room while it is still in the bracket and you do not gain much additional clearance since the brake lines restrict the movement.
5 - Remove the 6 T-20 torx screws connecting the EBCM and BPMV - 1 on each corner and 2 on the sides
6 - "Separate the EBCM from the BPMV by gently pulling apart until separated" - I should start laughing here, but it's not that funny. It's been my experience that anytime the instructions call for you to do something gently, nothing gentle is going to work. In this case, I had to use a flathead screw driver to brake the seal. Once it moved a little, the rest was easy. In addition to the rubber seal, each of the 12 holes have a peg in them from the BPMV. Don't go crazy, but be prepared to force them apart.
7 - At this point, all you've got to do is put it all back together. push the new EBCM onto the BPMV.
8 - Replace the 6 T-20 torx screws
9 - reconnect the wire harness
10 - put the intake back on

For EBCM repair/replace

Call Brandon

877-648-7530 at ABS FIXER
$150. plus UPS....warranted as long as You own it

 

i am having the same problem i took off the ecbm and sent it to Brandon, and he try to fix it, he does not have great success if your unit is 2000 or older, he does better with 2001 and up, mine was from a 2000 and this did not fix the problem. i just wish there was someone who sell refurb. or repair unit . still trying to fix my C1243H problem.

 

Thanks trussme for all that detail. Most helpful!
Still a few questions..
So if I understand you correctly the resistance measurments you speak of (and in manual page 5-166) are checking the internals of the BPMV (and not the EBCM) even though the "Pinout box" is connecting to the EBCM. Is this so?

Second since I like to be a DIY'er any idea where I can get a J41247 pinout box.

Third, looking at the EBCM connector diagram in the MY2000 manual (page 5-110) which pin corresponds to "terminal 8 of the J41247 pinout box?

Finally, you say have the car towed to have a TechII service. Does this mean there are no functional brakes if I bleed the ABS or just no ABS. Can I not pump the brakes bleeding oil at each brake pad as for a normal break fluid chance and have functional brakes but no active ABS. And drive there.

 

I would replace the EBCM 1st as it may be your problem source ...if Brandon @ abs fixer can't fix it, then there are a few replacement sources like Fred Beans & GM Parts Direct for
Part Number: 9367071
All 1999-2000 w/o Control Active Brakes: $486.40

...if C1243 does not come back after this ...your BPMV may be OK..otherwise, I would then take it in & have it replaced, rather than removing it, towing or driving without it on.

 

For what it is worth, it seems to me taking out the ETCM without the BPMV is not all that easy when the unit is in the front of the car i.e. 2000 and later. Without opening the oil lines (i.e. avoiding having to bring it to a service shop and have the oil flushed/reprogrammed) it seems you have to bend the lines to raise the whole unit up and out from the 3 supports. Also how the hell do you get to the 2 bolts nearest the oil lines?
If I open the oil lines I assume the unit has to be setup at a dealer, right?
Also somewhere I saw a picture on this forum of the EBCM unit and its socket. In that picture there was a second smaller socket/connector on the front face as well going vertically. On my unit there is only one (large) connector. Is that because I have no active handling?

 

I removed the EBCM from my 02 coupe and sent it in for repair and solved my particular problem. You don't need to open up any oil lines, the are six screws that hold it on and I believe there are 2 connectors. There are various instructions for removal on the forum. For myself it was a PITA but well worth the savings versus the dealer.
In your case, I'm not sure.

 

My '99 has to be about the most difficult. There are 5 screws that hold the module on. The fifth is not visible. It is under the rubber mount. The mounts on the module near the framerail are nearly impossible to loosen. I loosened one then lifted the entire assembly up a bit to then remove the ebtcm. It can be done, but the workspace is a bit cramped.