For 1990-2009 cars
ABS Components
Cell 44: PWR, GND, ABS Relays
Cell 14: G202 (1 of 3) (Buick)
Cell 14: G202 (1 of 3) (Oldsmobile)
Ground Distribution Schematics
Handling ESD Sensitive Parts Notice
Cell 10: IGN 1 Fuse, Ignition Switch
Cell 10: Battery Power
Cell 44: Stoplamp/BTSI Switch, Inlet/Outlet Solenoid Valves, and Wheel Speed Sensors
Cell 44: Stoplamp/BTSI Switch, Inlet/Outlet Solenoid Valves, and Wheel Speed Sensors
Cell 44: PWR, GND, ABS Relays

### Circuit Description

When the ignition is first turned to RUN, the EBCM/EBTCM goes through a self-check which lasts 2-4 seconds.

During this test, the EBCM/EBTCM grounds terminal 34. This energizes the main relay. Once the self-check is completed, the main relay remains energized. This delivers battery voltage to both the EBCM/EBTCM and the BPMV during vehicle operation. The constant voltage supply allows the vehicle to enter ABS mode without delay.

The main relay is de-energized whenever a system malfunction causes the amber ANTILOCK indicator to illuminate. This causes the ABS system to shut down.

### Conditions for Setting the DTC

DTC C1211 sets when the ignition switch is in RUN and battery voltage is not detected at the EBCM/EBTCM terminal 3 and/or terminal 33.

### Action Taken When the DTC Sets

The following actions are taken when the DTC sets:

• | A malfunction DTC is stored.

• | The ABS is disabled.

• | The ANTILOCK indicator is turned ON.

### Conditions for Clearing the DTC

The DTC will be cleared under following conditions:

• | Conditions for the malfunction are no longer present. Use the scan tool clear DTCs function.

• | 100 ignition switch key cycles have passed with no malfunctions detected.

### Diagnostic Aids

The following conditions may cause valve supply voltage interruption:

• | An open fuse

• | An open in any of the following circuits:

• | CKT 242

• | CKT 441

• | CKT 1632

• | CKT 1633

• | A short to ground in any of the following circuits:

• | CKT 242

• | CKT 441

• | CKT 1632

• | CKT 1633

• | A slow reacting or open main relay

A main relay that reacts slowly due to a mechanical malfunction may cause an intermittent DTC C1211. If the diagnostic table suggests replacing the EBCM/EBTCM, install a new relay and re-test the system before replacing the EBCM/EBTCM.

One of the following conditions may cause intermittent malfunctions:

• | A poor connection

• | Rubbed-through wire insulation

• | A wire that is broken inside the insulation

Inspect any suspect circuitry for the following conditions:

• | Backed out terminals

• | Improper mating

• | Broken locks

• | Improperly formed or damaged terminals

• | Poor terminal to wiring connections

• | Physical damage to the wiring harness

### Test Description

The numbers below refer to the step numbers in the diagnostic table.

1. This step checks for an open power feed for the solenoids internal to the BPMV.

2. This step ensures that the BPMV is not internally shorted to the ground.

3. This step checks the integrity of CKT 1633 to EBCM/EBTCM and the BPMV.

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Was the Diagnostic System Check performed? | -- | Go to Step 2 | Go to Diagnostic System Check
2 |

1. Turn the ignition switch to the OFF position.
2. Disconnect the BPMV connector C1.
3. Test the connector for proper terminal contact.
4. Use the J 39200 digital multimeter (DMM) in order to measure the resistance between the BPMV connector C1 terminal 13 and terminal 14.

Is the resistance less than the specified value?

2 ohms

Go to Step 3

Go to Step 17

3 | Measure the resistance between the BPMV connector C1 terminal 14 and the BPMV case. Is the resistance equal to the specified value? | OL (Infinite) | Go to Step 4 | Go to Step 17
4 |

1. Disconnect the EBCM/EBTCM connector.
2. Install the J 38716 pinout box.
3. Measure the resistance between the J 38716 terminal 1 and the ground.

Is the resistance less than the specified value?

2 ohms

Go to Step 5

Go to Step 18

5 |

1. Use a fused jumper in order to jump between the J 38716 terminal 1 and terminal 34.
2. Turn the ignition switch to the RUN position.

Does the ANTILOCK indicator turn OFF?

--

Go to Step 6

Go to Step 7

6 |

1. Measure the voltage between J 38716 terminals 1 and 3.
2. Measure the voltage between J 38716 terminal 1 and terminal 33.
3. Measure the voltage between the BPMV harness side connector C1 terminal 13 and the ground.
4. Measure the voltage between the BPMV harness side connector C1 terminal 14 and the ground.

Is the voltage on all of the measurements within the specified range?

Battery Voltage

Go to Step 28

Go to Step 19

7 |

1. Turn the ignition switch to the OFF position.
2. Remove the fused jumper.
3. Disconnect the ABS main relay.
4. Measure the resistance between the relay terminals 30 and 87A.

Is the resistance less than the specified value?

2 ohms

Go to Step 8

Go to Step 14

8 | Measure the resistance between the ABS main relay terminal 85 and terminal 86. Is the resistance within the specified range? | 40-90 ohms | Go to Step 9 | Go to Step 14
9 | Measure the resistance between the ABS main relay harness connector terminal 87A and the ground. Is the resistance less than the specified value? | 2 ohms | Go to Step 10 | Go to Step 20
10 | Measure the voltage between the ABS main relay harness connector terminal 87 and ground. Is the voltage within the specified range? | Battery Voltage | Go to Step 11 | Go to Step 21
11 |

1. Turn the ignition switch to the RUN position.
2. Measure the voltage between the ABS main relay harness connector terminal 86 and ground.

Is the voltage within the specified range?

Battery Voltage

Go to Step 12

Go to Step 24

12 |

1. Install the fused jumper between the ABS main relay harness connector terminal 30 and terminal 87.
2. Measure the voltage between the J 38716 terminal 33 and terminal 1.
3. Measure the voltage between the J 38716 terminal 3 and terminal 1.
4. Measure the voltage between the BPMV harness connector terminal 14 and the ground.
5. Measure the voltage between the BPMV harness connector terminal 13 and the ground.

Is the voltage on all of the measurements within the specified range?

Battery Voltage

Go to Step 13

Go to Step 24

13 |

1. Turn the ignition switch to the OFF position.
2. Install the fused jumper between the ABS main relay harness connector terminal 85 and terminal 86.
3. Turn the ignition switch to the RUN position.
4. Measure the voltage between the J 38716 terminal 34 and terminal 1.

Is the voltage within the specified range?

Battery Voltage

Go to Step 14

Go to Step 15

14 | Replace the ABS main relay. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check | --
15 | Remove and inspect the IP fuse block ABS (10A) fuse. Is the fuse open? | -- | Go to Step 16 | Go to Step 27
16 | Repair the short to ground in CKT 1632. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check | --
17 | Replace the BPMV. Refer to Brake Pressure Modulator Valve Replacement . Is the repair complete? | -- | Go to Diagnostic System Check | --
18 | Repair the open or high resistance in CKT 1451. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check | --
19 | Repair the open or high resistance in CKT 1633. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check | --
20 | Repair the open or high resistance in CKT 351. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check | --
21 | Remove and inspect the engine compartment fuse block ABS MAIN (30A) fuse. Is the fuse open? | -- | Go to Step 22 | Go to Step 23
22 | Repair the short to ground in CKT 1633 or CKT 242. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check | --
23 | Repair the open or high resistance in CKT 242. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check | --
24 | Remove and inspect the IP fuse block ABS (10A) fuse. Is the fuse open? | -- | Go to Step 25 | Go to Step 26
25 | Repair the short to ground in CKT 441. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check | --
26 | Repair the open or high resistance in CKT 441. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check | --
27 | Repair the open or high resistance in CKT 1632. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check | --
28 | Replace the EBCM/EBTCM. Refer to Electronic Brake and Traction Control Module Replacement . Is the repair complete? | -- | Go to Diagnostic System Check | --