DTC B1529. Cadillac SRX 2009

For 1990-2009 cars only

Makes 🢒 Cadillac 🢒 2009 🢒 SRX 🢒 Driver Information and Entertainment 🢒 Cellular, Entertainment, and Navigation 🢒 DTC B1529

DTC B1529 without N31

Diagnostic Instructions

•	Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

•	Review Strategy Based Diagnosis for an overview of the diagnostic approach.

•	Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC B1529 03: Device Voltage Reference Output Circuit Voltage Below Threshold

DTC B1529 07: Device Voltage Reference Output Circuit Voltage Above Threshold

Diagnostic Fault Information

Circuit	Short to Ground	Open/High Resistance	Short to Voltage	Signal Performance
B+ Voltage Reference	B1529 03	1	--	B1529 07
Right Steering Wheel Control Switch Signal	1	1	B3622 07	--
1. Steering Wheel Controls Inoperative

The body control module (BCM) supplies voltage to the audio steering wheel control switches and monitors the return signal. Each switch state is associated to a set resistance value and when pressed a specific voltage drop occurs across the resistor unique to the switch. The BCM identifies the switch selection and activates the feature.

Conditions for Running the DTC

•	Battery voltage is between 9-16 volts

•	The ignition is ON.

Conditions for Setting the DTC

B1529 03

•	The BCM detects a short to ground in the B+ voltage reference circuit.

•	The above condition is present for greater than 30 seconds.

B1529 07

•	The BCM detects a short to voltage in the B+ voltage reference circuit.

•	The above condition is present for greater than 30 seconds.

Action Taken When the DTC Sets

The BCM will ignore switch inputs.

Conditions for Clearing the DTC

•	The condition responsible for setting the DTC no longer exists.

•	A history DTC will clear once 100 consecutive malfunction free ignition cycles have occurred.

Reference Information

Electrical Information Reference

•	Circuit Testing

•	Connector Repairs

•	Testing for Intermittent Conditions and Poor Connections

•	Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

Ignition ON, observe the scan tool SWC Bank 1 status while pressing and releasing the switches. The reading should be SW1-SW10 identifying the switch pressed, and Idle when released.

Circuit/System Testing

Ignition OFF, disconnect the harness connector at the left and right steering wheel control switches.
Ignition ON, test for B+ between the voltage reference circuit terminal 1 and ground.

⇒	If less than the specified value, test the voltage reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.

Test for B+ between the voltage reference circuit terminal 1 and the signal circuit terminals listed below:

•	Steering wheel control switch signal circuit terminal 6 - left switch

•	Steering wheel control switch signal circuit terminal 2 - right switch

⇒	If less than the specified value, test the signal circuits for a short to voltage or an open/high resistance. If the circuits test normal, replace the BCM.

Ignition OFF, disconnect the X1 harness connector at the BCM.
Test for infinite resistance between ground and the signal circuit terminals listed below:

•	Steering wheel control switch signal circuit terminal 6 - left switch

•	Steering wheel control switch signal circuit terminal 2 - right switch

⇒	If less than the specified value, test the signal circuits for a short to ground.

Ignition ON, test for less than 1 volt between ground and the voltage reference circuit terminal 5 at the left steering wheel control switch.

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

Ignition ON, test for infinite resistance between ground and the voltage reference circuit terminal 5 at the left steering wheel control switch.

⇒	If not the specified value, test the voltage reference circuit for a short to ground.

Test for less than 1 ohm between the voltage reference circuit terminal 5 at the left steering wheel control switch and the voltage reference circuit terminal 5 at the right steering wheel control switch.

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

If all circuits test normal, test or replace the left or right steering wheel control switch.

Component Testing

Disconnect the harness connector at the right or left steering wheel control switch.
Connect a DMM between terminal 5 and terminal 6 (left switch) or terminal 2 (right switch) of either the left or right steering wheel control switches.

⇒	If any of the resistance measurements for the individual switches are not within the specified resistance values, replace the left or right steering wheel control switch.

Left Steering Wheel Switch Resistance

Function Switch	Minimum Resistance Value	Maximum Resistance Value
Source	787 Ohms	987 Ohms
No Switch Pressed	O.L.	O.L.

Right Steering Wheel Switch Resistance

Function Switch	Minimum Resistance Value	Maximum Resistance Value
Previous	534 Ohms	734 Ohms
Next	898k Ohms	1.25k Ohms
Volume Up	1.3k Ohms	1.5k Ohms
Volume Down	1.6k Ohms	1.8k Ohms
Mute/Voice Recognition	2.6k Ohms	3.0k Ohms
No Switch Pressed	O.L.	O.L.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

•	Steering Wheel Control Switch Assembly Replacement

•	Control Module References for BCM replacement, setup, and programming

DTC B1529 with N31