Diagnostic Instructions

DTC Descriptor

DTC B1370 01: Device Ignition 1 Circuit Short to Battery

DTC B1370 04: Device Ignition 1 Circuit Open Circuit

DTC B1380 01: Device Ignition ACCESSORY Circuit Short to Battery

DTC B1380 04: Device Ignition ACCESSORY Circuit Open Circuit

DTC B1441 01: Device Ignition OFF, RUN and CRANK Circuit Short to Battery

DTC B1441 06: Device Ignition OFF, RUN and CRANK Circuit Short to Ground or Open

Diagnostic Fault Information

Circuit	Short to Ground	Open/High Resistance	Short to Voltage	Signal Performance
Device Ignition 1 Circuit	B1370 04	B1370 04	B1370 01	--
Device Ignition ACCESSORY Circuit	B1380 04	B1380 04	B1380 01	--
Device Ignition OFF, RUN and CRANK Circuit	B1441 06	B1441 06	B1441 01	--

Conditions for Running the DTC

B1370 01

Ignition switch is in the OFF or ACC positions.

B1370 04

Ignition switch is in the START position.

B1380 01, B1380 04, B1441 01, B1441 06

The system voltage is 9-18 volts.

Conditions for Setting the DTC

B1370 01, B1380 01, B1441 01

BCM detects a short to battery.

B1370 04, B1380 04

The BCM detects an open.

B1441 06

The BCM detects an open or short to ground.

Conditions for Clearing the DTC

Reference Information

Schematic Reference

Connector End View Reference

Component Connector End Views

Description and Operation

Power Mode Description and Operation

Electrical Information Reference

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

With a scan tool, access Body Control Module, Power Mode data display list and compare all parameters listed with the corresponding ignition key position. The PMM Power Mode Parameters table below illustrates the correct state of these input parameters (circuits) in correspondence to the ignition switch position. The circuits which the individual parameters are related to are in parentheses.

PMM Power Mode Parameters

Ignition Switch Position	Current Power Mode	Run Relay Command (Off/Run Crank Voltage Circuit)	Ignition Switch Accessory Signal (Accessory Voltage Circuit)	Run/Crank Relay Command (Ignition 1 Voltage Circuit
Off Key Out	Off	Off	Inactive	OFF
Off Key IN	Off	Off	Inactive	OFF
Accessory	Accessory	Off	Active	OFF
Run	Run	ON	Active	ON
Start	Crank Request	OFF	Inactive	ON

Circuit/System Testing

Important: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

1. Inspect the Ignition Switch B+ fuse for an open.

⇒	If the fuse is open, test the circuits listed below for a short to ground:

•	Ignition switch B+

•	Accessory voltage

•	Off/Run crank voltage

•	Ignition 1 voltage

⇒	If all circuits test normal, replace the BCM.

2. Ignition OFF, disconnect the harness connector at the ignition switch.
3. Ignition ON, verify that a test lamp illuminates between the ignition switch B+ circuit terminal 2 and ground.

⇒	If the test lamp does not illuminate, test the B+ circuit for an open/high resistance.

Important: The ignition switch component test must be preformed before proceeding with this test to verify the integrity of the switch.

4. Ignition OFF, disconnect X2 and X4 harness connectors at the BCM.
5. Ignition key out, test for less than 1-volt between the circuit terminals listed below and ground:

•	Accessory voltage terminal C8

•	Ignition 1 voltage terminal D3

•	Off/Run/Crank voltage terminal 56

⇒	If greater than the specified range, test the circuit for a short to voltage.

6. Test for less than 1 ohm between the BCM terminals and the ignition switch terminals listed below:

•	Accessory voltage terminal C8 and 4

•	Ignition 1 voltage terminal D3 and 3

•	Off/Run/Crank voltage terminal 56 and 5

⇒	If greater than the specified range, test the circuit for an open/high resistance.

7. If all circuits test normal, replace the BCM.

Component Testing

Ignition Switch

Using the Resistance Test below, check the resistance between the pins of the ignition switch listed in each switch position listed.

Resistance Test

Ignition Switch Position	Terminals 2 and 3	Terminals 2 and 5	Terminals 2 and 6	Terminals 5 and 6
Off Key Out	Infinite	Infinite	Infinite	Infinite
Off Key IN	Infinite	< 5.0 ohms	Infinite	Infinite
Accessory	< 5.0 ohms	Infinite	Infinite	Infinite
Run	< 5.0 ohms	Infinite	Infinite	< 5.0 ohms
Start	Infinite	Infinite	Infinite	1275-1325 ohms

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.