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B3622



DTC B3622

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.



DTC Descriptors
DTC B3622 01
- Steering Wheel Controls Signal Circuit Short to Battery

DTC B3622 08
- Steering Wheel Controls Signal Circuit Signal Invalid

DTC B3622 59
- Steering Wheel Controls Signal Circuit Protection Timed Out




Diagnostic Fault Information






Circuit/System Description

The instrument panel module (IPM) supplies voltage to the multiple momentary contact switches and monitors the return signal. Each switch is associated to a set resistance value, when pressed a specific voltage drops across the resistors unique to the switch. The IPM identifies the selection, then sends a serial data message to the component controlled by the switch. If equipped with adaptive cruise control the Gap+/Gap- switches are in place of the mute/source switches and are in the same resistor ladder circuit.


Conditions for Running the DTC

* Voltage supplied to the module is in the normal operating voltage range of 9-16 volts.
* IPM in Accessory, Run or Crank power modes.



Conditions for Setting the DTC

B3622 01

The IPM detects a short to voltage on steering wheel controls signal circuit, for more than 5 seconds.

B3622 08

The IPM detected the signal from the steering wheel controls signal circuit does not fall into a calibrated range.

B3622 59

The IPM detects that any of the steering wheel control switches is stuck, for more than 30 seconds.


Action Taken When the DTC Sets

B3622 01 and 08

The IPM does not react to any switch inputs.

B3622 59

The IPM does not react to any switch inputs of equal or lower priority. If 2 switches are closed at the same time the IPM will read the least resistive path, so that switch takes precedence over the other one.


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.



Diagnostic Aids

Before diagnosis of the steering wheel controls, ensure the primary controls of the associated component are functioning properly.


Reference Information
Schematic Reference

Steering Wheel Secondary/Configurable Control Schematics (Steering Wheel Secondary/Configurable Control Schematics)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Steering Wheel Controls Description and Operation (Steering Wheel Controls Description and Operation)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning)


Circuit/System Verification

Ignition ON, observe the scan tool steering wheel controls counts while pressing the steering wheel control switch. The reading should change with each switch pressed and display counts when inactive.


Circuit/System Testing
Caution: Refer to SIR Caution (SIR Caution) .

Important: It is recommended that Component Testing be performed before Circuit Testing when diagnosing steering wheel controls.



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

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

3. Test for less than 0.5 volt between the signal circuit terminal 4 and ground.

If greater than 0.5 volt test the signal circuit for a short to voltage. If the circuit tests normal replace the IPM.

4. Install a 3-amp fused jumper wire at the ignition circuit terminal 1 at the left harness connector. Toggle the jumper wire between the signal circuit terminals 4 at the left and right harness connectors. Verify DTC B3622 sets.

If the DTC does not set, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the IPM.

5. Reconnect the left switch.
6. Test for B+ between the ignition terminal 1 and ground at the right harness connector.

If less than the specified value, test the ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal test or replace the left switch.

7. If all circuits test normal, test or replace the switch.



Component Testing

1. Ignition OFF, disconnect the harness connector at the steering wheel control switches.
2. Test the left switch for 2,360-2,400 ohms of resistance between the ignition circuit terminal 1 and the ignition circuit terminal 5.

If the resistance is not within the specified range, replace the faulty switch.

3. Test for infinite resistance between the ignition circuit terminal 1 and the signal circuit terminal 4 with the switch in the open position.

If less than infinite resistance, replace the switch.

4. Test resistance values between the ignition circuit terminal 1 and the signal terminal 4 with the switch closed in each position and verify readings are approximate to what the schematic reads.

If values do not match, replace the switch.




Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Steering Wheel Control Switch Assembly Replacement (Service and Repair)
* Control Module References (Programming and Relearning)for IPM replacement, setup, and programming