GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2005 🢒 STS 🢒 Vehicle Control Systems 🢒 Computer/Integrating Systems 🢒 DTC B1370

Circuit Description

The remote control door lock receiver (RCDLR) provides a high side drive output for the ignition 1 voltage circuit. The RCDLR controls the Run/Crank relay when the backup power mode is enabled.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B1370 Device Ignition 1 (ON and START) Circuit

DTC Symptom

DTC Symptom Descriptor

01

Short to Battery

02

Short to Ground

04

Open Circuit

Conditions for Running the DTC
    • Voltage supplied to the module is in the normal operating voltage range of 9-16 volts.
    • Backup power mode is enabled.

Conditions for Setting the DTC
    • The RCDLR detects a short to ground in the ignition 1 voltage circuit when the output is active.
    • The RCDLR detects a short to battery or an open in the ignition 1 voltage circuit when the output is inactive.
    • Any of the condition above must be present for more than 0.375 seconds.

Action Taken When the DTC Sets

The RCDLR disables the output for the current ignition cycle when a short to ground is detected.

Conditions for Clearing the DTC
    • A current DTC clears when the malfunction is no longer present.
    • A history DTC clears when the module ignition cycle counter reaches the reset threshold, without a repeat of the malfunction.

Step

Action

Yes

No

Schematic Reference: Power Distribution Schematics

Connector End View Reference: Master Electrical Component List

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

Was the DTC symptom 04?

Go to Step 7

Go to Step 3

3

Was the DTC symptom 02?

Go to Step 4

Go to Step 5

4
  1. Turn OFF the ignition.
  2. Disconnect the run/crank relay.
  3. Connect a test lamp across coil cavities of the run/crank relay.
  4. Turn ON the ignition, with the engine OFF.
  5. Retrieve the DTCs from the remote control door lock receiver (RCDLR).

Is the code still set as current?

Go to Step 5

Go to Step 14

5
  1. Turn OFF the ignition.
  2. Connect the run/crank relay, if previously disconnected.
  3. Disconnect the instrument panel module (IPM).
  4. Disconnect the ignition 1 voltage circuit at the IPM connector.
  5. Reconnect the IPM.
  6. Turn ON the ignition, with the engine OFF.
  7. Retrieve the DTCs from the RCDLR.

Is the code still set as current?

Go to Step 6

Go to Step 12

6
  1. Turn OFF the ignition.
  2. Disconnect the RCDLR.
  3. Disconnect the run/crank relay.
  4. Test the ignition 1 voltage circuit for a short to ground or short to voltage. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 15

Go to Step 10

7
  1. Turn OFF the ignition.
  2. Disconnect the run/crank relay.
  3. Connect a test lamp across coil cavities of the run/crank relay.
  4. Turn ON the ignition, with the engine OFF.
  5. Retrieve DTCs from RCDLR.

Is the code still set as current?

Go to Step 8

Go to Step 14

8
  1. Turn OFF the ignition.
  2. Test the ground circuit of the run/crank relay for an open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 15

Go to Step 9

9
  1. Disconnect the RCDLR.
  2. Test the ignition 1 voltage circuit between RCDLR and run/crank relay for an open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 15

Go to Step 10

10

Inspect for poor connections and terminal tension at the harness connector of the RCDLR module. Refer to Testing for Intermittent Conditions and Poor Connections .

Did you find and correct the condition?

Go to Step 15

Go to Step 11

11

Replace the RCDLR module. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 15

--

12

Inspect for poor connections and terminal tension at the harness connector of the IPM. Refer to Testing for Intermittent Conditions and Poor Connections .

Did you find and correct the condition?

Go to Step 15

Go to Step 13

13

Replace the IPM. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 15

--

14

Replace the run/crank relay.

Did you complete the replacement?

Go to Step 15

--

15
  1. Reconnect all components.
  2. Use the scan tool in order to clear the DTC.
  3. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

Go to Step 2

System OK