For 1990-2009 cars
ABS Components
Cell 44: PWR, GND, Pump Motor, Valve Solenoids, and Stoplamp/BTSI Switch
Cell 10: Battery and Underhood Fuse Blocks
Cell 10: MISC LGT, COOL FNS, C/LTR/RDO/CLSTR/MISC, ABS SOL and ABSMOT Fuses
Cell 10: ABS/CCR and CLG FAN/TCC Fuses
Handling ESD Sensitive Parts Notice

### Circuit Description

The UART serial data link allows information to be exchanged from module to module as needed. This is done by the PCM, the PCM requests and sends all the information that is transmitted on the UART line. When a scan tool is connected to the UART line it takes over for the PCM and sends and requests the needed information.

### Diagnostic Aids

• | Thoroughly inspect the wiring and the connectors. Failure to carefully and fully inspect the wiring and the connectors can result in misdiagnosis. Misdiagnosis may cause replacement of parts without repairing the malfunction.

• | If an intermittent malfunction exists, refer to Intermittents and Poor Connections Diagnosis in Wiring Systems.

#### No Communication with EBCM/EBTCM

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
DEFINITION: Scan tool can not communicate with the EBCM/EBTCM.
1 | Was the Diagnostic System Check performed? | -- | Go to Step 2 | Go to Diagnostic System Check
2 | Turn the ignition switch to the RUN position with the engine off. Can the scan tool communicate with other modules on the UART serial data line, such as the PCM? | -- | Go to Step 3 | Go to Data Link Communications System Check
3 | Inspect the 10A ABS/CCR fuse in the IP fuse block. Is the fuse OK? | -- | Go to Step 4 | Go to Step 9
4 | Inspect the 40A ABS SOL fuse in the LH underhood fuse block. Is the fuse OK? | -- | Go to Step 12 | Go to Step 5
5 |

1. Install a new ABS SOL fuse.
2. Recheck the fuse.

Is the fuse OK?

--

Go to Diagnostic System Check

Go to Step 6

6 |

1. Turn the ignition switch to the OFF position.
2. Remove the ABS SOL fuse.
3. Disconnect the EBCM/EBTCM connector.
4. Connect the J 39700 universal pinout box using the J 39700-25 cable adapter to the EBCM/EBTCM harness connector only.
5. Using the J 39200 DMM, measure the resistance between terminals D and B of the J 39700 .

Is the resistance equal to the specified value?

OL (infinite)

Go to Step 7

Go to Step 8

7 | Replace the EBCM/EBTCM. Refer to Electronic Brake Control Module Replacement . Is the replacement complete? | -- | Go to Diagnostic System Check | --
8 | Repair CKT 342 for a short to ground. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check | --
9 |

1. Install a new 10A ABS/CCR fuse.
2. Cycle the ignition switch from the OFF to RUN position, engine off.
3. Recheck the fuse.

Is the fuse OK?

--

Go to Diagnostic System Check

Go to Step 10

10 |

1. Turn the ignition switch to the OFF position.
2. Remove the 10A ABS/CCR fuse.
3. Disconnect the EBCM/EBTCM connector.
4. Connect the J 39700 universal pinout box using the J 39700-25 cable adapter to the EBCM/EBTCM harness connector only.
5. Using the J 39200 DMM, measure the resistance between terminals A and B of the J 39700 .

Is the resistance equal to the specified value?

OL (infinite)

Go to Step 7

Go to Step 11

11 | Repair CKT 641 for a short to ground. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check | --
12 |

1. Install the fuses if removed.
2. Turn the ignition switch to the RUN position, engine off.
3. Using the J 39200 DMM, measure the voltage at the 10A ABS/CCR fuse by probing between the fuse test terminals and a good ground.

Is the voltage within the specified range?

Battery Voltage

Go to Step 13

Go Wiring Repairs in Wiring Systems

13 | Using the J 39200 DMM, measure the voltage at the 40A ABS SOL fuse by probing between the fuse test terminals and a good ground. Is the voltage within the specified range? | Battery Voltage | Go to Step 14 | Go Wiring Repairs in Wiring Systems
14 |

1. Turn the ignition switch to the OFF position.
2. Disconnect the EBCM/EBTCM connector.
3. Connect the J 39700 universal pinout box using the J 39700-25 cable adapter to the EBCM/EBTCM harness connector only.
4. Using the J 39200 DMM, measure the resistance between the J 39700 terminal B and a good ground.

Is the resistance less than the specified value?

2 ohms

Go to Step 16

Go to Step 15

15 | Repair CKT 1050 or G106 for an open or high resistance. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check | --
16 |

1. Turn the ignition switch to the RUN position, engine off.
2. Using the J 39200 DMM, measure the voltage between the J 39700 terminals A and B.

Is the voltage within the specified range?

Battery Voltage

Go to Step 18

Go to Step 17

17 | Repair CKT 641 for an open. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check | --
18 | Using the J 39200 DMM, measure the voltage between J 39700 terminals D and B. Is the voltage within the specified range? | Battery Voltage | Go to Step 7 | Go to Step 19
19 | Repair CKT 342 for an open. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check | --