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For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2005 🢒 CTS 🢒 Accessories 🢒 Navigation Systems 🢒 DTC U2153

Circuit Description

The vehicle information communication system (VICS) Module Assembly communicates with the navigation radio over 2 circuits. These are the VICS (+) circuit, and the VICS (-) circuit.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC U2153 Navigation Electronic Control Unit (ECU) - VICS Communication Circuit

Conditions for Running the DTC
    • The vehicle must be equipped with the VICS Module Assembly. This system is available only on export vehicles and is dealer installed.
    • The navigation radio must detect a power mode transition from OFF-ASLEEP to ON.
    • The navigation radio does not set this DTC if B1327 or B1328 is current.

Conditions for Setting the DTC

There is no response from the VICS module when queried by the navigation radio after successfully initializing the system.

The navigation radio does not receive information from the VICS module when the radio detects a power mode transition to ON.

Action Taken When the DTC Sets

The VICS switch disappears from the navigation system menu.

Conditions for Clearing the DTC

The navigation radio receives a response from the VICS module.

Test Description

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

  1. This step determines if the malfunction is present.

    2.

  2. This step verifies that the DTC sets under normal operating systems.

Step

Action

Yes

No

Schematic Reference: Navigation System Schematics

Connector End View Reference: Navigation System Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

  1. Turn OFF the ignition.
  2. Open, then close driver door to cancel retained accessory power (RAP).

    3. Important: Do not operate any vehicle system for one minute.

  3. Connect a scan tool.
  4. Turn ON the ignition with engine off.
  5. Retrieve DTCs from the navigation radio.

Does the DTC reset?

Go to Step 3

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

3

Test the vehicle information communication system (VICS) (+) circuit for the following:

    • An open
    • A short to ground
    • A short to voltage
    • High resistance

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 4

4

Test the VICS (-) circuit for the following:

    • An open
    • A short to ground
    • A short to voltage
    • High resistance

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 5

5

Inspect for poor connections at the harness connectors of the VICS Module Assembly. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 6

6

Inspect for poor connections at the harness connectors of the navigation radio. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 7

7

Replace the VICS Module Assembly. Refer to the VICS dealer installation instructions.

Did you find and correct the condition?

Go to Step 9

Go to Step 8

8

Replace the navigation radio. Refer to Control Module References in Computer/Integrating Systems.

Did you complete the repair?

Go to Step 9

--

9
  1. Use the scan tool to clear the DTCs.
  2. Operate the vehicle as specified within the Conditions for Running the DTC in the supporting text.

Does the DTC reset?

Go to Step 2

System OK