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For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 1997 🢒 Catera 🢒 DTC 🢒 DTC 48 System Voltage Out of Range

Object Number: 174415 Size: SF
ABS Components
Antilock Brake System Schematics

Circuit Description

The EBTCM is required to operate within a specified range of voltage to function properly. It monitors the ignition feed circuit to determine if the voltage falls below a minimum level or above a maximum level.

Conditions for Setting the DTC
    • The EBTCM operating voltage falls below 9.4 volts out of ABS/TCS control, or 8.8 volts during ABS/TCS control.
    • The EBTCM operating voltage rises above 17.4 volts out of ABS/TCS control.
    • The low voltage or the high voltage is detected for more than 500 milliseconds with the vehicle speed above 6 km/h (3.6 mph).

Action Taken When the DTC Sets
    • A malfunction DTC is stored.
    • The ABS/TCS valves are switched passive, which prevents a possible pump start-up.
    • The ABS and the TC indicator lamps are turned on.
    • The ABS/TCS remains active.

Conditions for Clearing the DTC
    • The condition for the DTC is no longer present.
    • The scan tool Clear DTCs function is used.
    • 100 drive cycles have passed with no DTCs detected.

Diagnostic Aids

Perform a thorough inspection of the wiring. Perform a thorough inspection of the connectors. Failure to carefully and fully inspect the wiring and the connectors may result in misdiagnosis. Misdiagnosis causes part replacement with reappearance of the malfunction.

Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

  1. This step checks if the voltage is above the maximum of the range.

    2.

  2. This step checks if the voltage is below the minimum of the range.

    3.

  3. This step checks for an open in the ignition input circuit.

    4.

  4. This step checks for a short to ground in the ignition input circuit.

DTC 48 - System Voltage Out of Range

Step

Action

Value(s)

Yes

No

1

Was a Diagnostic System Check performed?

--

Go to Step 2

Go to A Diagnostic System Check

2
  1. Turn all the accessories off.
  2. Install a scan tool.
  3. Start the engine.
  4. Use the scan tool to monitor the battery voltage while running the engine at approximately 2000 RPM.

Is the monitored battery voltage within the specified range?

0-17.4 V

Go to Step 4

Go to Step 3

3

Use a J 39200 DMM to measure the voltage between the battery positive terminal and ground.

Is the voltage within the specified range?

0-17.4 V

Go to Step 5

Go to Starting System Check in Engine Electrical

4

Continue to monitor the battery voltage with the scan tool while running the engine at approximately 2000 RPM.

Is the monitored battery voltage within the specified range?

0-9.4 V

Go to Step 6

Go to Step 5

5
  1. Turn the ignition switch to the OFF position.
  2. Disconnect the scan tool if still connected.
  3. Test drive the vehicle above 6 km/h (3.5 mph).

Did DTC 48 reset?

--

Go to Step 14

Go to A Diagnostic System Check

6

Use a J 39200 DMM to measure the voltage between the battery positive terminal and ground.

Is the voltage within the specified range?

0-9.4 V

Go to Starting System Check in Engine Electrical

Go to Step 7

7
  1. Turn the ignition switch to the OFF position.
  2. Remove and inspect the 10 amp ABS fuse 19.

Is the fuse open?

--

Go to Step 8

Go to Step 9

8

Use a J 39200 DMM to measure the resistance between each of the ABS fuse block terminals and ground.

Is the resistance for both terminals within the specified range?

OL (Infinite)

Go to Step 11

Go to Step 10

9
  1. Reinstall the fuse.
  2. Disconnect the 4-pin EBTCM connector C2 from the EBTCM.
  3. Turn the ignition switch to the RUN position with the engine off.
  4. Use a J 39200 DMM to measure the voltage between terminal 1 and ground.

Is the voltage within the specified range?

Battery Voltage

Go to Step 12

Go to Step 15

10
  1. Disconnect the 4-pin EBTCM connector C2 from the EBTCM.
  2. Use a J 39200 DMM to measure the resistance between the 4-pin EBTCM connector C2, terminal 1 and ground.

Is the resistance within the specified range?

OL (Infinite)

Go to Step 14

Go to Step 16

11
  1. Install a new fuse.
  2. Test drive the vehicle above 6 km/h (3.5 mph).
  3. Turn the ignition switch to the OFF position.
  4. Recheck the fuse.

Is the fuse open?

--

Go to Step 14

Go to A Diagnostic System Check

12
  1. Turn the ignition switch to the OFF position.
  2. Inspect the 4-pin EBTCM connector and inspect the terminals, especially terminal 1, for the following:
    3. • Inspect for poor terminal contact.
    • Inspect for corrosion.
  3. Check that the connector is properly retained to the EBTCM when connected.

Are the following signs evident:

    • Is poor terminal contact evident?
    • Is corrosion evident?
    • Is damage evident?

--

Go to Step 17

Go to Step 13

13
  1. Reconnect the connector.
  2. Turn the ignition switch to the OFF position.
  3. Disconnect the scan tool if the scan tool is still connected.
  4. Test drive the vehicle above 6 km/h (3.5 mph).

Did DTC 48 reset?

--

Go to Step 14

Go to A Diagnostic System Check

14

Replace the EBTCM. Refer to EBTCM Replacement .

Is the repair complete?

--

Go to A Diagnostic System Check

--

15

Repair an open in CKT FA202. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to A Diagnostic System Check

--

16

Repair a short to ground in CKT FA202. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to A Diagnostic System Check

--

17

Replace all the terminals or replace the connector that exhibits the following signs:

    • Replace the connector that exhibits signs of poor terminal contact.
    • Replace the connector that exhibits signs of corrosion.
    • Replace the connector that exhibits signs of damaged terminals.

Refer to Connector Repairs or Repairing Connector Terminals in Wiring Systems.

Is the repair complete?

--

Go to A Diagnostic System Check

--