The Wrench

Jacking the rear wheels up, putting the car in 2nd gear, and easing up to 9 MPH fires the motor, and also fires the solenoids in the BPMV.

I know you've heard all the remedies, but this one worked really well for me when the others failed.

I had the stalled motor code 1243 coming on more and more often.
I initially used the method of separating the modules and probing pin 8 with 12 volts to run the motor for short periods. But this does not fire the solenoids, and just circulates old brake fluid around in the BPMV.
This worked pretty well for a couple years, only had the problem about every 6 months. But over time it increased in frequency. I even drilled a small hole in the module case and soldered a wire to the pin 8 connection, so I could just apply 12 volts to the wire without even touching the module (2000's are a bear to get to).
Well, this method finally stopped working well, as I would exercise the motor, and the next week the code came back.

So, I tried the "jack-up" method about a month ago - ran the rear wheels up to 9 MPH and let the ABS run for about 5-10 seconds. Did this about 10 times, with short cool-off periods.
NO MORE 1243 CODES FOR OVER A MONTH NOW - SO FAR SO GOOD.

My theory is that working the solenoids moves fresh brake fluid into the module passages, and maybe helps free up the pump?
Or, it could just be I'm driving it a bit more in the warmer weather, keeping the battery charged more. We'll see.

Oh, another theory; if the motor is dragging, it will put a much heavier load on the relay in the EBCM, and possibly damage it over time.
So, if you have a stalled motor code 1243, better try to loosen it up before activating the traction control and ABS in spirited driving or track days.

Man, I hope someone comes up with a fix for these '97-'00 ABS units.
I saw one out of a '99 on eBay yesterday for $1500 - probably on it's last legs too.

DG

the prof

Well, going to the gas station and have the car lifted and give it a try, wish me luck.

The prof

Bill Curlee

I drive my car aggressively and activate AH a few times a week. I also exercise my Antilock Brakes whenever the streets are WET.

Find a safe flat straight isolated road and from 40-50 mph,, mash the brakes till lock up/ABS actuation. The wet roads will allow for easier tire slippage and antilock operation without as much tire wear and suspension abuse.


Frequent use keeps the BPMV motor and solenoids in tip top shape.

THE WRENCH

I like you ABS exercise plan also. Simple enough and effective.

the prof

Hey Wrench, it was raining out here in Crime Free Oakland,CA today so I was out spinning the rear tires hopeing to start up the motor but no luck. going to the chevy place to have them try your trick. Mainly cuz I could not find a gas station that had a lift that I could drive on to, yeah I know $ $ $ but it be what it be.

Did give them some grief though, because they said the EBCM was bad but since it pointed to the motor I am hopeing to get a break on the price,... yeah, when pigs fly. anyway I'll let ya know what happens.
tomorrow, say a prayer for me,...

The prof

the prof

Well,.... I gave them detailed instructions and they did not follow them. The short story is that I had to reseat the connector, replace the 40 amp fuse they blew and repair the + lead that goes right across the motor that they hit with a tool and thats what blew the fuse.

So, I called chevy customer service (HQ) and told them my story and that I will NEVER ! ! ! go to them for service EVER ! I said I could have this kind of service at a gas station ! BTW the whole 15 min. conversation was recorded by them, maybe something will come of it.

The Prof

the prof

This worked great, the grenn wire on top of the motor is the power lead to the motor. Run a lead from the + of the battery with a sharp point at the other end , put an insulator under the wire on the pump, stick the probe into the green wire for 1-2 seconds, the motor should start to turn. Now it will get hot ! at first so give it a cool down for a few seconds and try again, if you hear the motor starting to turn just keep powering up for 1-2 seconds, 15 second cool down and hopefully like I just found out on mine, it took about 8 on/off runs and then it ran just fine for a few seconds. So I put the leads away got in the car, started it up and PRESTO ! NO LIGHTS it is raining here so took it out for a spin and ABS/TRACTION CONTROL works again !

scooby99

I tried this on my 99 and I'm still getting the c1243 code. Should I try the 12v to the green wire atop the motor? No rain in sight, so the lock up procedure is out, unless I try a gravel road (not sure I want to do that). Anyone have any good ideas?

Thanks,

Sam

the prof

Hey scooby99, yes try powering up the abs motor like I described in the post just before this one. just remember it will draw a lot of power so just 1 to 2 seconds and the motor should turn over. May have to do this a few times. Mine smoked a little but there is no option short of pulling the assembly out. Let me know how it works out.

The Prof

Donutz

I want to try doing the 12 V to the ABS motor to see if it will work for me. Where exactly is the ABS motor on the 1999 model?

scooby99

It is located in front of the power steering pump on top of the steering rack.

Sam

Bill Curlee

It looks like this but yours will be in front between the Rad and the engine on the drivers side:

Donutz

Oh wow! That was fast! Thank you very much!!!
Yours is VERY clean too!!! So, where is this green wire that I gotta hook a 12V supply upto?!?!?

Bill Curlee

LOL

That is a demo chassis at the Bowling Green Museaum

You need to remove the EBTCM from the BPMV and probe the female contacts in the BPMV

Donutz

Hmmm, Ok, If it rains this weekend, I may try to figure that out!

the prof

On a 99 not sure. It will be the motor that is attached to a block where all the brake lines are connected. Just remember to do a real quick touch to it, it may smoke a bit but no problem, DON'T leave it connected for more than 1 second, it's going to get hot REAL FAST !

You can do it 2 times but I'd wait 15 minutes until you try it again.

Also you may have to do this a few times over a week and it may not last but at least you got it to spin over.

I still have it come on from time to time.
Good luck

froggy47

Old thread, I know, but YIKES they put the abs between the exhaust pipes!!! What year(s)?

Bill Curlee

Rear mounted EBTCM were only in 97 and early year 98 cars. In mid to late 98 they moved it to the front.

BC

froggy47

Thanks Bill

the prof

Had the same problem but had to replace the unit anyway. If you hunt around you can find 1 for 1000.00. One problem is that after install you really have to bleed the brakes a few times to get all the air out, doing a couple of drive a round's to work the air to a point where it can be bled out. Just keep working on it to get that hard pedal back.

Cybermind

Or use a Tech2. Actuating the pump and fully bleeding the system can be done properly with the push of a button. Tech2 clones are now only about $300. Best money I ever spent.