C1243 Code
Thread Starter
1st Gear
Joined: Mar 2008
Posts: 1
Likes: 0
From: Staunton Virginia
C1243 Code
Have Traction Control and ABS warning lights on and C1243 code. Replaced blown 40 amp fuse for ABS, but still have codes. Have read a lot about EBTCM failure, but not with this code. Please help!
Le Mans Master
Joined: May 2006
Posts: 7,890
Likes: 262
From: Hillsboro OR
C1243 states the brake pump motor is either stalled or turning slowly. The pump motor is inside the BPMV (Brake Pressure Modulator Valve). It is not serviceable. 
The BMPV is bolted onto the EBCM. The two halves can be separated. Not great news but, I hope that helps. 
The BMPV is bolted onto the EBCM. The two halves can be separated. Not great news but, I hope that helps.
Tech Contributor
Joined: Oct 1999
Posts: 41,063
Likes: 9,827
From: Charlotte, NC (formerly Endicott, NY)
DTC C1243 BPMV Pump Motor Stalled
Circuit Description
When the pump motor relay is grounded by the EBCM, it closes and provides battery voltage to operate the pump.
Conditions for Setting the DTC
DTC C1243 can be set when the pump motor relay has been commanded off after the pump motor has been on. A malfunction has occurred if the pump motor was on, and the EBCM sensed a stuck or slowly turning pump motor.
Action Taken When the DTC Sets
ABS/TCS/Active Handling (if equipped with RPO JL4) are disabled.
Indicators that turn on:
ABS indicator
Car Icon (TCS indicator)
Messages displayed on the DIC:
Service ABS
Service Traction System
Service Active HNDLG (if equipped with Active Handling RPO JL4)
Conditions for Clearing the DTC
Condition for DTC is no longer present and scan tool clear DTC function is used.
Fifty ignition cycles have passed with no DTCs detected.
Diagnostic Aids
It is very important that a thorough inspection of the wiring and connectors be performed. Failure to carefully and fully inspect wiring and connectors may result in misdiagnosis, causing part replacement with reappearance of the malfunction.
An intermittent malfunction can be caused by poor connections, broken insulation, or a wire that is broken inside the insulation.
If an intermittent malfunction exists refer to Testing for Electrical Intermittents in Wiring Systems.
Test Description
The numbers below refer to step numbers on the diagnostic table.
3. Checks for good pump motor ground.
5. Checks for good pump motor ground through the BPMV.
DTC C1243 BPMV Pump Motor Stalled Step
Action
Value(s)
Yes
No
1
Was the Diagnostic System Check performed?
--
Go to Step 2
Go to Diagnostic System Check - ABS
2
Is DTC 1217 also set as a current DTC?
--
Go to DTC C1217 Pump Motor Relay Contact Circuit Open
Go to Step 3
3
Turn the ignition switch to the OFF position.
Using the J 39200 DMM, measure the resistance between the pump motor ground stud and a good chassis ground.
Is the resistance within the range specified in the value(s) column?
0-2 ohms
Go to Step 4
Go to Step 9
4
Disconnect the EBCM connector.
Remove the EBCM from the BPMV.
Inspect the EBCM to BPMV connector for conditions which could cause intermittents, such as damage, corrosion, poor terminal contact, or presence of brake fluid.
Is connector OK and cavity free of brake fluid?
--
Go to Step 5
Go to Step 6
5
Install the J 41247 Pinout Box to the BPMV connector.
Using the J 39200 DMM, measure the resistance between the J 41247 terminal 8 and the pump motor ground stud.
Is the resistance within the range specified in the Value(s) column?
0.2-10 ohms
Go to Step 7
Go to Step 8
6
If connector corrosion or damage is evident, replace BPMV and/or EBCM as necessary.
If brake fluid is present, replace BPMV and EBCM.
Is the replacement complete?
--
Go to Diagnostic System Check - ABS
--
7
Replace the EBCM. Refer to Electronic Brake Control Module (EBCM) Replacement .
Is the replacement complete?
--
Go to Diagnostic System Check - ABS
--
8
Replace the BPMV. Refer to Brake Pressure Modulator Valve (BPMV) Replacement .
Is the replacement complete?
--
Go to Diagnostic System Check - ABS
--
9
Repair open or high resistance in CKT 1250. Refer to Wiring Repairs in Wiring Systems.
Is the repair complete?
--
Go to Diagnostic System Check - ABS
--
Bill
Circuit Description
When the pump motor relay is grounded by the EBCM, it closes and provides battery voltage to operate the pump.
Conditions for Setting the DTC
DTC C1243 can be set when the pump motor relay has been commanded off after the pump motor has been on. A malfunction has occurred if the pump motor was on, and the EBCM sensed a stuck or slowly turning pump motor.
Action Taken When the DTC Sets
ABS/TCS/Active Handling (if equipped with RPO JL4) are disabled.
Indicators that turn on:
ABS indicator
Car Icon (TCS indicator)
Messages displayed on the DIC:
Service ABS
Service Traction System
Service Active HNDLG (if equipped with Active Handling RPO JL4)
Conditions for Clearing the DTC
Condition for DTC is no longer present and scan tool clear DTC function is used.
Fifty ignition cycles have passed with no DTCs detected.
Diagnostic Aids
It is very important that a thorough inspection of the wiring and connectors be performed. Failure to carefully and fully inspect wiring and connectors may result in misdiagnosis, causing part replacement with reappearance of the malfunction.
An intermittent malfunction can be caused by poor connections, broken insulation, or a wire that is broken inside the insulation.
If an intermittent malfunction exists refer to Testing for Electrical Intermittents in Wiring Systems.
Test Description
The numbers below refer to step numbers on the diagnostic table.
3. Checks for good pump motor ground.
5. Checks for good pump motor ground through the BPMV.
DTC C1243 BPMV Pump Motor Stalled Step
Action
Value(s)
Yes
No
1
Was the Diagnostic System Check performed?
--
Go to Step 2
Go to Diagnostic System Check - ABS
2
Is DTC 1217 also set as a current DTC?
--
Go to DTC C1217 Pump Motor Relay Contact Circuit Open
Go to Step 3
3
Turn the ignition switch to the OFF position.
Using the J 39200 DMM, measure the resistance between the pump motor ground stud and a good chassis ground.
Is the resistance within the range specified in the value(s) column?
0-2 ohms
Go to Step 4
Go to Step 9
4
Disconnect the EBCM connector.
Remove the EBCM from the BPMV.
Inspect the EBCM to BPMV connector for conditions which could cause intermittents, such as damage, corrosion, poor terminal contact, or presence of brake fluid.
Is connector OK and cavity free of brake fluid?
--
Go to Step 5
Go to Step 6
5
Install the J 41247 Pinout Box to the BPMV connector.
Using the J 39200 DMM, measure the resistance between the J 41247 terminal 8 and the pump motor ground stud.
Is the resistance within the range specified in the Value(s) column?
0.2-10 ohms
Go to Step 7
Go to Step 8
6
If connector corrosion or damage is evident, replace BPMV and/or EBCM as necessary.
If brake fluid is present, replace BPMV and EBCM.
Is the replacement complete?
--
Go to Diagnostic System Check - ABS
--
7
Replace the EBCM. Refer to Electronic Brake Control Module (EBCM) Replacement .
Is the replacement complete?
--
Go to Diagnostic System Check - ABS
--
8
Replace the BPMV. Refer to Brake Pressure Modulator Valve (BPMV) Replacement .
Is the replacement complete?
--
Go to Diagnostic System Check - ABS
--
9
Repair open or high resistance in CKT 1250. Refer to Wiring Repairs in Wiring Systems.
Is the repair complete?
--
Go to Diagnostic System Check - ABS
--
Bill
