C1243 DC current measurements
1st Gear
Joined: Sep 2005
Posts: 1
Likes: 0
I've had similar results. I power-cycled my BPCM pump motor about one year ago and it is now throwing the code again. But when I power-cycled it this time, it never really loosened up much and the code remained. I figured that the brake fluid must be pretty gummed up in there and that it needs a good flushing with fresh fluid.
Would you provide some instructions on how you flushed your BPCM with new brake fluid?
Thanks, ....Dave
Thread Starter
Instructor
Joined: Jul 2008
Posts: 145
Likes: 2
From: Macon NC
I built an execiser to do the whole thing from the driver seat (do you live close to North Carolina)but I can give you the basics and with a some wire and a switch you can pump fresh fluid through motor and it should clean it out. I have not had a reoccurrence of the problem since I did that two years ago. Send me a PM and I will get you started.
4th Gear
Joined: Dec 2022
Posts: 4
Likes: 0
From: Santa Fe, NM
Works!! Thank you!
I have a 98 with rear mounted EBCM/BMTV and just finished the exercise routine (thanks Bill Curlee) that has been referenced in earlier posts. Since mine was rear mounted I chose to use a battery charger as a 12 volt source and since I am a retired electrical engineer I added a DC current meter into the circuit to see what was really the condition voltage and current wise with a stuck motor and what happens afterward.
I used a fairly large wire to keep it from heating and used a spade lug to plug into pin 8.
I used the 10 amp setting on my VOM as it was the highest scale I had I also used the leads from the amp meter as a switch to apply the voltage to the motor.
Results: The initial meter reading was greater than 10 amps and the voltage from the battery charger dropped to under 10 volts. The motor ran but was indeed slow.
I continued to run it in short bursts and eventually the current came down to 5 amps and the voltage stayed at 12+ volts.
Here is a video of the final run. You can hear the motor run. It will take
55 seconds to down load with high speed.
Observations: I am a retired IBMer and based on my experience with analog and digital circuits I think what happens when C1243 is posted: the computer has sensed that the current going to the motor is higher than a predetermined setting and assumes the motor is stuck. A DC motor will draw high current when the armature is not turning and the result is the voltage drops. I think for this type of repair it is probably better to use a battery charger rather than your battery as you want to start with a lower inital current until the armature starts turning at speed. This will save the internal circuit in the BTMV (they are called land patterns) and keeps from heating the wire. If you monitor the curernt and it drops to 5 to 6 amps ( you can read this on the battery charger) then you are done.
If you want more information send me a PM.
I used a fairly large wire to keep it from heating and used a spade lug to plug into pin 8.
I used the 10 amp setting on my VOM as it was the highest scale I had I also used the leads from the amp meter as a switch to apply the voltage to the motor.
Results: The initial meter reading was greater than 10 amps and the voltage from the battery charger dropped to under 10 volts. The motor ran but was indeed slow.
I continued to run it in short bursts and eventually the current came down to 5 amps and the voltage stayed at 12+ volts.
Here is a video of the final run. You can hear the motor run. It will take
55 seconds to down load with high speed.
Observations: I am a retired IBMer and based on my experience with analog and digital circuits I think what happens when C1243 is posted: the computer has sensed that the current going to the motor is higher than a predetermined setting and assumes the motor is stuck. A DC motor will draw high current when the armature is not turning and the result is the voltage drops. I think for this type of repair it is probably better to use a battery charger rather than your battery as you want to start with a lower inital current until the armature starts turning at speed. This will save the internal circuit in the BTMV (they are called land patterns) and keeps from heating the wire. If you monitor the curernt and it drops to 5 to 6 amps ( you can read this on the battery charger) then you are done.
If you want more information send me a PM.
First sharpened a piece of welding rod to connect/pierce into the Green Wire on the pump. Used my battery charger on the 2 amp setting. Once contact from the charger to the rod the motor started, I repeated the process three times at
three minute intervals. Rod got hot until amp
draw dropped to less 5. Your instructions are
Excellent! Now the ABS works!
Last edited by Ortegb01; Dec 4, 2022 at 05:38 PM. Reason: Spelling
2nd Gear
Joined: Oct 2023
Posts: 2
Likes: 0
From: Moorhead, MN
I will be running through this process on my 2000 in the next couple of weeks and will keep you posted on the outcome. I thought about removing the EBCM over the winter to solder the 5 points that throw the C1214 code. Is that worth breaking into if I am not displaying that error yet?
