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For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 1998 🢒 DeVille 🢒 DTC 🢒 DTC C1285 Lateral Accelerometer Sensor Circuit Malfunction

Object Number: 413325 Size: MF
ABS Components
Cell 44: Stabilitrak® Sensors and ICCS Data Link
Handling ESD Sensitive Parts Notice

Circuit Description

The lateral accelerometer output is measured by the EBTCM when the ignition is ON. The usable output voltage range for the lateral accelerometer is 0.25-4.75 volts. The scan tool will report a zero lateral accelerometer signal of 2.5 volts if no sensor bias (offset) is present.

Conditions for Setting the DTC

All of the following conditions occur:

    • The ignition is ON.
    • The lateral accelerometer input is less than 0.15 volts or greater than 4.85 volts for more than 1 second.

Action Taken When the DTC Sets
    • A malfunction DTC is stored.
    • Stabilitrak® is disabled.
    • The DIC displays the SERVICE STABILITY SYS message.
    • The ABS/TCS remain functional.

Conditions for Clearing the DTC
    • The condition for DTC is no longer present and you used scan tool Clear DTCs function.
    • The condition for DTC is no longer present and you used the On-Board Clear DTCs function.
    • The EBTCM does not detect the DTC in 50 drive cycles.

Diagnostic Aids
    • During diagnosis, park the vehicle on a level surface.
    • Find out from the driver under what conditions the DTC was set (when the DIC displayed the SERVICE STABILITY SYS message). This information will help to duplicate the failure.
    • Thoroughly inspect the wiring and the connectors. An incomplete inspection of the wiring and the connectors may result in a misdiagnosis, causing a part replacement with the reappearance of the malfunction.
    • Poor connections, broken insulation, or a break in the wire inside the insulation may cause an intermittent malfunction.
    • If an intermittent malfunction exists, refer to Intermittents and Poor Connections in Wiring Systems.

DTC C1285 Lateral Accelerometer Sensor Circuit Malfunction

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 EBTCM connector.
  3. Install the J 39700 universal pinout box using the J 39700-25 cable adapter to the EBTCM harness connector only.
  4. Using the J 39200 digital multimeter (DMM), measure the resistance between the J 39700 terminal 22 and terminal B.

Is the resistance equal to the specified value?

OL (infinite)

Go to Step 4

Go to Step 3

3

Repair CKT 715 for a short to ground. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Diagnostic System Check

--

4

Using the J 39200 DMM, measure the resistance between the J 39700 terminal 11 and terminal B.

Is the resistance equal to the specified value?

OL (infinite)

Go to Step 6

Go to Step 5

5

Repair CKT 1337 for a short to ground. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Diagnostic System Check

--

6

Using the J 39200 DMM, measure the resistance between the J 39700 terminal 27 and terminal B.

Is the resistance equal to the specified value?

OL (infinite)

Go to Step 8

Go to Step 7

7

Repair CKT 1338 for a short to ground. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Diagnostic System Check

--

8

Using the J 39200 DMM, measure the resistance between the J 39700 terminal 11 and terminal 27.

Is the resistance equal to the specified value?

OL (infinite)

Go to Step 10

Go to Step 9

9

Repair short between CKT 1337 and CKT 1338. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Diagnostic System Check

--

10

Using the J 39200 DMM, measure the resistance between the J 39700 terminal 11 and terminal 22.

Is the resistance equal to the specified value?

OL (infinite)

Go to Step 12

Go to Step 11

11

Repair short between CKT 1337 and CKT 715. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Diagnostic System Check

--

12

Using the J 39200 DMM, measure the resistance between the J 39700 terminal 27 and terminal 22.

Is the resistance equal to the specified value?

OL (infinite)

Go to Step 14

Go to Step 13

13

Repair short between CKT 1338 and CKT 715. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Diagnostic System Check

--

14
  1. Turn the ignition switch to the RUN position, engine OFF.
  2. Using the J 39200 DMM, measure the voltage between the J 39700 terminal 22 and terminal B.

Is the voltage greater than the specified value?

1 V

Go to Step 15

Go to Step 16

15

Repair CKT 715 for a short to voltage. Refer to DTC P1566 Engine RPM Too High - Cruise Control Disabled in Wiring Systems.

Is the repair complete?

--

Go to Diagnostic System Check

--

16

Using the J 39200 DMM, measure the voltage between the J 39700 terminal 11 and terminal B.

Is the voltage greater than the specified value?

1 V

Go to Step 17

Go to Step 18

17

Repair CKT 1337 for a short to voltage. 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 the J 39700 terminal 27 and terminal B.

Is the voltage greater than the specified value?

1 V

Go to Step 19

Go to Step 20

19

Repair CKT 1338 for a short to voltage. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Diagnostic System Check

--

20
  1. Turn the ignition switch to the OFF position.
  2. Connect a fused jumper wire between terminal 22 and terminal B of the J 39700 .
  3. Disconnect the lateral accelerometer connector.
  4. Using the J 39200 DMM, measure the resistance between the lateral accelerometer harness connector terminal B and a good ground.

Is the resistance less than the specified value?

2 ohms

Go to Step 22

Go to Step 21

21

Repair CKT 715 for an open or high resistance. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Diagnostic System Check

--

22
  1. Connect a fused jumper wire between terminal 27 and terminal B of the J 39700 .
  2. Using the J 39200 DMM, measure the resistance between the lateral accelerometer harness connector terminal C and a good ground.

Is the resistance less than the specified value?

2 ohms

Go to Step 24

Go to Step 23

23

Repair CKT 1338 for an open or high resistance. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Diagnostic System Check

--

24
  1. Connect a fused jumper wire between terminal 11 and terminal B of the J 39700 .
  2. Using the J 39200 DMM, measure the resistance between the lateral accelerometer harness connector terminal A and a good ground.

Is the resistance less than the specified value?

2 ohms

Go to Step 26

Go to Step 25

25

Repair CKT 1337 for an open or high resistance. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Diagnostic System Check

--

26
  1. Install the J 39700 universal pinout box using the J 39700-25 cable adapter to the EBTCM and the EBTCM harness connector.
  2. Reconnect the lateral accelerometer.
  3. Remove the fused jumper wire from the J 39700 .
  4. Turn the ignition switch to the RUN position, engine OFF.
  5. Using the J 39200 DMM, measure the voltage between the J 39700 terminal 11 and terminal 27.

Is the voltage within the specified range?

4.5-5.5 V

Go to Step 27

Go to Step 32

27

Using the J 39200 DMM, measure the voltage between the J 39700 terminal 22 and terminal B.

Is the voltage within the specified range?

2.35-2.65 V

Go to Step 28

Go to Step 30

28

Using the J 39200 DMM, measure the voltage between the J 39700 terminal 22 and terminal 27.

Is the voltage within the specified range?

2.35-2.65 V

Go to Step 29

Go to Step 27

29

Using a scan tool, read the lateral accelerometer value in volts.

Is the voltage within the specified range?

2.0-3.0 V

Go to Step 30

Go to Step 32

30

Replace the lateral accelerometer. Refer to Lateral Accelerometer Replacement .

Is the replacement complete?

--

Go to Step 31

--

31
  1. Read the diagnostic aids and conditions for setting the DTC.
  2. Cycle the ignition switch from the OFF to the RUN position.
  3. Carefully drive the vehicle above 24 km/h (15 mph) for several minutes, while monitoring a scan tool for ABS/TCS/ICCS DTCs.

Did DTC C1285 set as a current DTC while the vehicle was being driven?

--

Go to Step 32

Go to Diagnostic System Check

32

Replace the EBTCM. Refer to Electronic Brake Control Module Replacement .

Is the replacement complete?

--

Go to Diagnostic System Check

--