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For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 1998 🢒 Seville 🢒 DTC 🢒 DTC B1658 EEPROM Checksum Error

Circuit Description

The steering column tilt/telescoping module (TTM) calibrations are stored in the EEPROM. When the ignition is first turned ON, the TTM performs internal tests on the EEPROM and can determine the integrity of its non-volatile memory. The TTM compares its previously stored checksum with the checksum calculated when the ignition is first turned ON. If the two checksums do not match, the TTM indicatesthat a calibration malfunction (checksum error) is current.

Conditions for Setting the DTC
    • The stored checksum does not match the calculated checksum.
    • The TTM detects an internal memory malfunction (checksum error).
    • The condition must occur when the ignition is first turned ON.

Action Taken When the DTC Sets
    • Stores a DTC B1658 in the TTM memory.
    • No driver warning message are displayed for this DTC.
    • The TTM usees default values for any memory address in the EEPROM that is corrupt.

Conditions for Clearing the DTC
    • This DTC requires an ignition cycle in order to change from current to history.
    • The TTM no longer detects an internal memory malfunction (checksum error).
    • A history DTC clears after 50 consecutive ignition cycles if the condition for the malfunction is no longer present.
    • Use the On-Boards clearing DTCs feature.
    • Use a scan tool.

Diagnostic Aids

Since the EEPROM cannot be removed from the TTM and DTC B1658 is an internal TTM malfunction, the TTM may need to be replaced. Refer to diagnostic table.

Test Description

The numbers below refer to the step numbers on the diagnostic table:

  1. Perform the Tilt/Telescoping Steering Column Diagnostic System Check before continuing with the diagnosis of this DTC.

    2.

  2. Clear all DTCs and cycle ignition to check that the DTC did not falsely set.

    3.

  3. Clear all DTCs after the repair procedure is complete.

DTC B1658 TTM -- EEPROM Checksum Error

Step

Action

Value(s)

Yes

No

1

Was the Tilt/Telescoping Steering Column Diagnostic System Check performed?

--

Go to Step 2

Go to Tilt/Telescoping Steering Column Diagnostic System Check

2

  1. Turn ON the ignition switch.
  2. Clear any DTCs. Refer to Clearing DTCs.
  3. Turn OFF the ignition switch.
  4. Turn ON the ignition switch.

Is the DTC still present?

--

Go to Step 3

System OK

3

Replace the steering column tilt/telescoping module. Refer to Tilt/Telescoping Module Replacement .

Is the replacement complete?

--

Go to Step 4

--

4

  1. Turn OFF the ignition switch.
  2. Reconnect or install any connectors or components that were disconnected or removed.
  3. Turn ON the ignition switch.
  4. Clear any DTCs.
  5. Repeat the Diagnostic System Check. Refer to Tilt/Telescoping Steering Column Diagnostic System Check .

Is the Diagnostic System Check complete?

--

System OK

--