DTC B1B1A or B1B1B
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 B1B1A Left 3rd Row Seat Recline Switch Signal DTC B1B1B Right 3rd Row Seat Recline Switch Signal Symptom Byte Information: Symptom Byte List Diagnostic Fault Information
| Circuit Number | Circuit Function | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performan |
|---|---|---|---|---|---|
| 2698 | Signal | B1B1A:11 | B1B1A:15 | B1B1A:15 | B1B1A:1C |
| 2699 | Signal | B1B1B:11 | B1B1B:15 | B1B1B:15 | B1B1B:1C |
| 6474 | Ground | — | B1B1A:15, B1B1B:15 | — | — |
Circuit/System Description The power folding third row seat system consists of folding seat switches, a control module, a seat back release actuator, a hall-effect position sensor, and the folding seat motor. The third row folding seat switches are located on the D-pillar. Voltage to the switches is supplied through the park enable relay while in a de-energized state. The park enable relay is controlled by the body control module (BCM) through a high side drive control circuit and will be de-energized whenever the ignition is in the accessory or run positions and the transmission is in park. Battery voltage is supplied to the folding seat control module through a 30 A fuse located in the rear body fuse block. When a folding seat switch is pressed, battery voltage is applied through the switch contacts and the signal circuit to the folding seat control module indicating the folding seat request. In response to this signal, the module applies a PWM voltage through the seat back release actuator control circuit energizing the actuator. With the actuator energized and the seat back released, the control module applies battery voltage and ground through the folding seat motor control circuits to the motor. The motor runs to either move the seat back cushion to the folded or unfolded seat position. The control module supplies the hall-effect sensor with a low reference and a signal circuit. The module monitors the voltage from the signal circuit in order to detect a seat stall condition. If the module does not detect seat movement within 400ms, it will cease folding seat operation. Conditions for Running the DTC Ignition ON Conditions for Setting the DTC B1B1A 11 or B1B1B 11 The K169 Folding 3rd Row Seat Module detects a short to ground on the signal circuit. B1B1A 15 or B1B1B 15 The K169 Folding 3rd Row Seat Module detects a short to voltage or an open/high resistance on the signal circuit. B1B1A 1C or B1B1B 1C The K169 Folding 3rd Row Seat Module detects a voltage that is out of range on the signal circuit. Action Taken When the DTC Sets The K169 Folding 3rd Row Seat Module will disable all seat functions. Conditions for Clearing the DTC The DTC clears when the diagnostic runs and passes. The history DTC will clear after 40 consecutive fault-free ignition cycles have occurred. Reference Information Schematic Reference Rear Seat Schematics Connector End View Reference Master Electrical Component List Description and Operation Power Seats System Description and Operation 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.
- Verify DTC B1B1A and/or B1B1B is not set. ⇒ If the DTC is set Refer to Circuit/System Testing. ⇓ If the DTC is not set
- A fault is currently not present and may be an intermittent condition. Circuit/System Testing
- Ignition OFF, disconnect the connector at the S144B 3rd Row Seat Folding Switch - Rear Compartment.
- Test for less than 10 Ω between the low reference circuit terminal 4 and ground: ⇒ If 10 Ω or greater 2.1. Test circuit 6474 for a open/high resistance. ⇒ If an open/high resistance is found, repair the fault on the circuit. ⇓ If an open/high resistance is not found 2.2. Replace the K169 Folding 3rd Row Seat Module. ⇓ If less than 10 Ω
- Ignition/Vehicle in Service Mode.
- Test for 4.8–5.2 Volts between signal circuit terminal 1 and ground. ⇒ If less than 4.8 V 4.1. Test circuit 2698 for a short to ground. ⇒ If a short to ground is found, repair the fault on the circuit. ⇓ If a short to ground is not found 4.2. Test circuit 2698 for an open/high resistance. ⇒ If an open/high resistance is found, repair the fault on the circuit. ⇓ If an open/high resistance is not found 4.3. Replace the K169 Folding 3rd Row Seat Module. ⇒ If greater than 5.2 V 4.1. Test circuit 2698 for a short to voltage. ⇒ If a short to voltage is found, repair the fault on the circuit. ⇓ If a short to voltage is not found 4.2. Replace the K169 Folding 3rd Row Seat Module. ⇓ If between 4.8–5.2 V
- Test for 4.8–5.2 Volts between signal circuit terminal 6 and ground. ⇒ If less than 4.8 V 5.1. Test circuit 2699 for a short to ground. ⇒ If a short to ground is found, repair the fault on the circuit. ⇓ If a short to ground is not found 5.2. Test circuit 2699 for an open/high resistance. ⇒ If an open/high resistance is found, repair the fault on the circuit. ⇓ If an open/high resistance is not found 5.3. Replace the K169 Folding 3rd Row Seat Module. ⇒ If greater than 5.2 V 5.1. Test circuit 2699 for a short to voltage. ⇒ If a short to voltage is found, repair the fault on the circuit. ⇓ If a short to voltage is not found 5.2. Replace the K169 Folding 3rd Row Seat Module. ⇓ If between 4.8–5.2 V
- Replace the S144B 3rd Row Seat Folding Switch - Rear Compartment. Repair Instructions Perform the Diagnostic Repair Verification after completing the repair. Control Module References for K169 Folding 3rd Row Seat Module replacement, programming, and setup.