Got Code C1243 bad BPMV need advice!
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Joined: May 2005
Posts: 63
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From: Cayucos CA
Got Code C1243 bad BPMV need advice!
$%&^, I got the service ABS, traction and active handling lamps on the DIC. Got it checked out at my mech. (not the dealer) It threw codes C1226, C1243, C1277 he cleared them out then right away it threw only C1243. The BPMV pump motor stalled out every time! Anyone know if it really is the motor or any on those sensors like the ABS one that might make the motor stall. I NEVER got the code C1214! I can afford to fix it but I don't want to get a new BPMV motor if its really just a sensor thats broke.
If I end up getting a new BPMV motor then where is a good place to get a new one or can I have mine rebuild or something?
I forgot to say that my copper battery connectors are corroded and one is almost ready to brake off. Guess thats a good place to start though I don't know if it will help anything.
If I end up getting a new BPMV motor then where is a good place to get a new one or can I have mine rebuild or something?
I forgot to say that my copper battery connectors are corroded and one is almost ready to brake off. Guess thats a good place to start though I don't know if it will help anything.
Last edited by DuffC5; Jun 16, 2007 at 05:26 PM. Reason: Forgot something to say
Tech Contributor
Joined: Oct 1999
Posts: 41,013
Likes: 9,775
From: Charlotte, NC (formerly Endicott, NY)
It could be either the EBCM, the BPMV or some bad connections when you get this code. The pump motor being stalled or moving slowly could indicate a bad pump or a bad voltage source from the EBCM. You need to run some checks before buying parts.
Here is the diagnostic procedure:
DTC C1242 or C1243
Circuit Description
The system relay is energized when the ignition is ON. The system relay supplies voltage to the solenoid valves and the pump motor. This voltage is referred to as the system voltage.
The electronic brake control module (EBCM) controls each solenoid valve by grounding the solenoid.
The EBCM controls the pump motor by grounding the control circuit. The pump serves 2 purposes:
Transfers brake fluid from the brake calipers to the master cylinder reservoir during pressure decrease events.
Transfers brake fluid from the master cylinder reservoir to the brake calipers during pressure increase events.
Conditions for Running the DTC
C1242
The system voltage is greater than 8.0 volts.
The system relay is ON.
The pump motor is commanded OFF.
C1243
The pump motor is ON for at least 0.3 seconds.
The system relay is ON.
Conditions for Setting the DTC
C1242
The voltage across the pump motor is between 1.7 - 10.2 volts for 2 seconds.
C1243
The pump motor is stalled or turning slowly.
Action Taken When the DTC Sets
If equipped, the following actions occur:
The EBCM disables the ABS/TCS/VSES for the duration of the ignition cycle.
The DRP does not function optimally.
The ABS indicator turns ON.
The Traction Control and Active Handling indicator turns ON.
The DIC displays the following messages:
Service ABS
Service Traction System
Service Active Handling
Conditions for Clearing the DTC
The condition for the DTC is no longer present and the DTC is cleared with a scan tool.
The EBCM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles.
Diagnostic Aids
The pump motor is integral to the BPMV. The pump motor is not serviceable.
Test Description
The number below refers to the step number on the diagnostic table.
3. Tests the ability of the EBCM to control the pump motor. If the test lamp illuminates, the pump motor circuit within the EBCM is good.
Step
Action
Yes
No
Schematic Reference: ABS Schematics
Connector End View Reference: ABS Connector End Views
1
Did you perform the ABS Diagnostic System Check?
Go to Step 2
Go to Diagnostic System Check - ABS
2
Install a scan tool.
Turn ON the ignition, with the engine OFF.
Use the scan tool in order to clear the DTCs.
With the scan tool, perform the Automated Test.
Does the DTC reset?
Go to Step 3
Go to Testing for Intermittent and Poor Connections in Wiring Systems
3
Turn OFF the ignition.
Disconnect the pump motor harness pigtail connector of the BPMV.
Connect a test lamp between the pump motor circuits at the pump motor connector of the EBCM using the J 35616-A connector test adapter kit.
Use the scan tool in order to clear the DTCs.
With the scan tool, perform the Pump Motor Test.
Does the test lamp illuminate?
Go to Step 4
Go to Step 5
4
Inspect for poor connections at the pump motor harness pigtail connector of the BPMV. Refer to Testing for Intermittent and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 8
Go to Step 6
5
Inspect for poor connections at the harness connector of the EBCM. Refer to Testing for Intermittent and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 8
Go to Step 7
6
Replace the BPMV. Refer to Brake Pressure Modulator Valve (BPMV) Replacement .
Did you complete the repair?
Go to Step 8
--
7
Replace the EBCM. Refer to Electronic Brake Control Module (EBCM) Replacement .
Did you complete the repair?
Go to Step 8
--
8
Use the scan tool in order to clear the DTCs.
With the scan tool, perform the Automated Test.
Does the DTC reset?
Go to Step 2
System OK
Bill
Here is the diagnostic procedure:
DTC C1242 or C1243
Circuit Description
The system relay is energized when the ignition is ON. The system relay supplies voltage to the solenoid valves and the pump motor. This voltage is referred to as the system voltage.
The electronic brake control module (EBCM) controls each solenoid valve by grounding the solenoid.
The EBCM controls the pump motor by grounding the control circuit. The pump serves 2 purposes:
Transfers brake fluid from the brake calipers to the master cylinder reservoir during pressure decrease events.
Transfers brake fluid from the master cylinder reservoir to the brake calipers during pressure increase events.
Conditions for Running the DTC
C1242
The system voltage is greater than 8.0 volts.
The system relay is ON.
The pump motor is commanded OFF.
C1243
The pump motor is ON for at least 0.3 seconds.
The system relay is ON.
Conditions for Setting the DTC
C1242
The voltage across the pump motor is between 1.7 - 10.2 volts for 2 seconds.
C1243
The pump motor is stalled or turning slowly.
Action Taken When the DTC Sets
If equipped, the following actions occur:
The EBCM disables the ABS/TCS/VSES for the duration of the ignition cycle.
The DRP does not function optimally.
The ABS indicator turns ON.
The Traction Control and Active Handling indicator turns ON.
The DIC displays the following messages:
Service ABS
Service Traction System
Service Active Handling
Conditions for Clearing the DTC
The condition for the DTC is no longer present and the DTC is cleared with a scan tool.
The EBCM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles.
Diagnostic Aids
The pump motor is integral to the BPMV. The pump motor is not serviceable.
Test Description
The number below refers to the step number on the diagnostic table.
3. Tests the ability of the EBCM to control the pump motor. If the test lamp illuminates, the pump motor circuit within the EBCM is good.
Step
Action
Yes
No
Schematic Reference: ABS Schematics
Connector End View Reference: ABS Connector End Views
1
Did you perform the ABS Diagnostic System Check?
Go to Step 2
Go to Diagnostic System Check - ABS
2
Install a scan tool.
Turn ON the ignition, with the engine OFF.
Use the scan tool in order to clear the DTCs.
With the scan tool, perform the Automated Test.
Does the DTC reset?
Go to Step 3
Go to Testing for Intermittent and Poor Connections in Wiring Systems
3
Turn OFF the ignition.
Disconnect the pump motor harness pigtail connector of the BPMV.
Connect a test lamp between the pump motor circuits at the pump motor connector of the EBCM using the J 35616-A connector test adapter kit.
Use the scan tool in order to clear the DTCs.
With the scan tool, perform the Pump Motor Test.
Does the test lamp illuminate?
Go to Step 4
Go to Step 5
4
Inspect for poor connections at the pump motor harness pigtail connector of the BPMV. Refer to Testing for Intermittent and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 8
Go to Step 6
5
Inspect for poor connections at the harness connector of the EBCM. Refer to Testing for Intermittent and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 8
Go to Step 7
6
Replace the BPMV. Refer to Brake Pressure Modulator Valve (BPMV) Replacement .
Did you complete the repair?
Go to Step 8
--
7
Replace the EBCM. Refer to Electronic Brake Control Module (EBCM) Replacement .
Did you complete the repair?
Go to Step 8
--
8
Use the scan tool in order to clear the DTCs.
With the scan tool, perform the Automated Test.
Does the DTC reset?
Go to Step 2
System OK
Bill
Burning Brakes
Joined: Jan 2006
Posts: 1,170
Likes: 27
From: Magnolia Greens NC
Some Advice...
The EBCM sits between the engine and radiator. The EBCM has the large wire harness coming into it and the sticker on top. The Brake Pressure Modulator Valve (BPMV) has the brake lines coming out. The EBCM is a dry module, meaning that you can change it out without having to worry about bleeding the ABS system. All of the brake fluid is contained within the BPMV. The coils fit over small spools that have valves inside them. The valves are operated by an electromagnetic field supplied by the coils.
Start by doing a quick visual inspection of the wires. If there are any obvious signs of damage, you've likely found the problem. One member had a problem with the wires rubbing the serpentine belt
Also check to make sure the wire harness has a good connection. If the connection appears solid disconnect it (see step 3 in the replacement instructions below) check the pins to ensure that they have not been bent or damaged in any way. If there is any sign of corrosion, clean it off. Once everything looks good, reseat the harness.
Next, let's move on to the grounds. The EBCM is grounded to the chassis on the left frame rail, just forward of the engine. It's the Black box. As you can see, it's real easy for dirt and moisture to get in that area which isn't exactly good for electronic components. Even if you never drive your car in the rain, it'll still get wet when you wash it, and that could be enough
Start by unbolting the chassis ground, then take the chassis ground connector apart.
Corrosion can build up in the ground connector. If your chassis grounds look bad, you may have found the problem. Even if they don't, go ahead and clean it up with a wire brush before putting it back together. Also clean off the chassis and bolt to make sure you've got a good clean ground.
If you are having any other electrical issues, it's a good idea to check the grounds.
It's unlikely, but before you break out you credit card and forking over your hard earned money, it's a good idea to check the fuses. One fuse box is located under the hood beside the battery, the second one is under the passenger side of the dash. Remove the floor mat and you will see the access panel. Just pull the fuses out and do a quick visual check At this point, we know all of the wires are good, but for some reason enough voltage is not getting to the system. It is possible that your battery is not functioning properly. If your battery is a couple of years old, has been drained and recharged a couple of times it might be a good idea to go ahead and replace your battery. This is a long shot for EBCM issues, but I think it's worth a shot before spending several hundred dollars for a new EBCM and you're going to have to replace it eventually. Old batteries can cause a variety of minor electrical issues and you likely have a bunch of history codes for minor issues if the battery is causing the problem.
Now the EBCM itself. If the electrical contacts inside the relay are dirty or burnt, the vibration from striking the module may change the symptoms or may clear them up for a while. This is by no means a fix or a cure all, in fact it could make it worse or it may not do anything, it's just something to try. Use a small plastic hammer or something similar, lightly tap the front of the EBCM on the lower right corner of the module. The area will be on the right hand side of the lower electrical connection seen in the picture below.
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. 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" - 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
At this point, the AH/TC/ABS should work normally. If not, you've also got a problem with the BPMV. Although you could replace the BPMV yourself, you have to bleed the ABS system which requires Tech II. For those 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 want have to pay the mechanic to diagnose the problem for you.
Start by doing a quick visual inspection of the wires. If there are any obvious signs of damage, you've likely found the problem. One member had a problem with the wires rubbing the serpentine belt
Also check to make sure the wire harness has a good connection. If the connection appears solid disconnect it (see step 3 in the replacement instructions below) check the pins to ensure that they have not been bent or damaged in any way. If there is any sign of corrosion, clean it off. Once everything looks good, reseat the harness.
Next, let's move on to the grounds. The EBCM is grounded to the chassis on the left frame rail, just forward of the engine. It's the Black box. As you can see, it's real easy for dirt and moisture to get in that area which isn't exactly good for electronic components. Even if you never drive your car in the rain, it'll still get wet when you wash it, and that could be enough
Start by unbolting the chassis ground, then take the chassis ground connector apart.
Corrosion can build up in the ground connector. If your chassis grounds look bad, you may have found the problem. Even if they don't, go ahead and clean it up with a wire brush before putting it back together. Also clean off the chassis and bolt to make sure you've got a good clean ground.
If you are having any other electrical issues, it's a good idea to check the grounds.
It's unlikely, but before you break out you credit card and forking over your hard earned money, it's a good idea to check the fuses. One fuse box is located under the hood beside the battery, the second one is under the passenger side of the dash. Remove the floor mat and you will see the access panel. Just pull the fuses out and do a quick visual check At this point, we know all of the wires are good, but for some reason enough voltage is not getting to the system. It is possible that your battery is not functioning properly. If your battery is a couple of years old, has been drained and recharged a couple of times it might be a good idea to go ahead and replace your battery. This is a long shot for EBCM issues, but I think it's worth a shot before spending several hundred dollars for a new EBCM and you're going to have to replace it eventually. Old batteries can cause a variety of minor electrical issues and you likely have a bunch of history codes for minor issues if the battery is causing the problem.
Now the EBCM itself. If the electrical contacts inside the relay are dirty or burnt, the vibration from striking the module may change the symptoms or may clear them up for a while. This is by no means a fix or a cure all, in fact it could make it worse or it may not do anything, it's just something to try. Use a small plastic hammer or something similar, lightly tap the front of the EBCM on the lower right corner of the module. The area will be on the right hand side of the lower electrical connection seen in the picture below.
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. 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" - 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
At this point, the AH/TC/ABS should work normally. If not, you've also got a problem with the BPMV. Although you could replace the BPMV yourself, you have to bleed the ABS system which requires Tech II. For those 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 want have to pay the mechanic to diagnose the problem for you.
