Pinpoint Test AF: Functional Test - Third Row Power Seat
Seats
Pinpoint Tests
Pinpoint Test AF: Functional Test - Third Row Power Seat
Refer to Wiring Diagram Set 120, Power Seats for schematic and connector information. Diagrams By Number
Normal Operation
The Third Row Power Seat Functional Test checks the complete seat for correct operation and functionality. This pinpoint test focuses of those faults which affect operation of both seats.
- B2794 (3rd Row Power Fold Circuit Failure) - sets when the Smart Junction Box (SJB) detects an open or short to battery in circuit CPS58 (WH/BN).
- B2A2D (3rd Row Power Fold Circuit Short to Ground ) - sets when the SJB detects a short to ground in circuit CPS58 (WH/BN).
This pinpoint test is intended to diagnose the following:
- Fuse(s)
- Wiring, terminals or connectors
- Third row power seat relay
- Seat control switch
- PFSM
- SJB
PINPOINT TEST AF: FUNCTIONAL TEST - THIRD ROW POWER SEAT
NOTICE: The following pinpoint test uses a test light to simulate normal circuit loads. Use only the test light recommended in the Special Tools table. To avoid connector terminal damage, use the Flex Probe Kit for the test light probe connection to the vehicle. Do not use the test light probe directly on any connector.
NOTE: Verify good battery condition before diagnosing the Power-Fold Seat Module (PFSM) system. Poor battery condition may interfere with PFSM operation. If battery voltage drops below 10 volts, seat movement does not start. If battery voltage drops below 8 volts, a started seat movement stops.
NOTE: The accessory delay system (courtesy lamps) times-out after 10 minutes and disables the third row power seat operation. Meter voltage measurements may be inaccurate when this occurs, which could lead to misdiagnosis. To enable the accessory delay system during diagnosis and testing, close and open any vehicle door.
NOTE: Very cold weather conditions can cause the power-fold mechanisms to bind resulting in incorrect seat operation. In cold weather, allow the seat to warm up before checking seat operation.
NOTE: The Smart Junction Box (SJB) may also be identified as the Generic Electronic Module (GEM).
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AF1 CHECK SEAT(S) OPERATION
- Check the seat(s).
- Verify the vehicle is in PARK and liftgate open to enable the system and access the seat control switch. To diagnose an inoperative power liftgate, refer to Body Closures Testing and Inspection.
- Check the LIFTGATE AJAR warning indicator on the IC module display. If the warning indicator is not illuminated, the power-fold seat system may not be enabled due to a concern with the liftgate ajar switch circuitry (part of courtesy lighting system). Refer to Interior Lighting Testing and Inspection to diagnose the courtesy lamps do not turn on with the liftgate open.
- Verify no objects/obstructions are present between, below, in front or in back of the seats.
- Select BOTH using the seat select button.
- Operate the seats to each position (NORMAL, STOW, FOLD and TAILGATE) allowing the seats to complete each selection.
- Does either seat move to any position?
Yes
If both seats operate to each selected position correctly, GO to AF2 for additional checks.
If only the LH seat does not operate correctly, GO to Pinpoint Test AG. Pinpoint Test AG: Seat Latch Motor and Latch Switch Functional Test - LH Third Row Power Seat
If only the RH seat does not operate correctly, GO to Pinpoint Test AH. Pinpoint Test AH: Seat Latch Motor and Latch Switch Functional Test - RH Third Row Power Seat
If both seats move but neither seat correctly obtains all the selected positions, GO to AF19.
No
GO to AF3.
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AF2 CHECK THE OPERATION OF EACH SEAT SEPARATELY
- Check the seats.
- Select LH using the seat select button and operate the seat to each position (NORMAL, STOW, FOLD and TAILGATE) allowing the seat to complete each selection.
- Select RH using the seat select button and operate the seat to each position allowing the seat to complete each selection.
- Do both seats operate correctly?
Yes
The system is operating correctly at this time. CHECK for causes of an intermittent concern such as loose, corroded or disconnected connectors, pinched or damaged wiring and REPAIR as necessary.
No
GO to AF13.
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AF3 CHECK THE SJB FOR DTCs
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test - SJB.
- Are DTCs present?
Yes
For DTC B2794 GO to AF10.
For DTC B2A2D, GO to AF11.
For any other DTCs, REFER to Multifunction Electronic Modules Testing and Inspection.
No
GO to AF4.
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AF4 CHECK FOR VOLTAGE AND GROUND TO THE PFSM
- Disconnect: PFSM C4250A.
- To access the PFSM, refer to the appropriate steps in Power-Fold Seat Module (PFSM) Power-Fold Seat Module (PFSM).
- Verify the vehicle is in PARK and the liftgate is open.
- Verify the courtesy lights are on. If needed, close and open any door on the vehicle.
- Measure the voltage between PFSM C4250A-8, circuit CBB18 (GY/OG), harness side and PFSM C4250A-10, circuit GD149 (BK/GY), harness side.
- Is the voltage greater than 10 volts?
Yes
GO to AF12.
No
GO to AF5.
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AF5 CHECK THE PFSM FOR VOLTAGE
- Verify the vehicle is in PARK and the liftgate is open.
- Verify the courtesy lights are on. If needed, close and open any door on the vehicle.
- Measure the voltage between PFSM C4250A-8, circuit CBB18 (GY/OG), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
REPAIR circuit GD149 (BK/GY) for an open. TEST the system for normal operation.
No
GO to AF6.
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AF6 CHECK THE THIRD ROW POWER SEAT RELAY FOR VOLTAGE AND GROUND
- Disconnect: Third Row Power Seat Relay.
- Verify the vehicle is in PARK and the liftgate is open.
- Verify the courtesy lights are on. If needed, close and open any door on the vehicle.
- Measure the voltage between third row power seat relay socket pin 2, circuit CLN09 (YE/GN), and third row power seat relay socket pin 1, circuit GD120 (BK/GN).
- Is the voltage greater than 10 volts?
Yes
GO to AF8.
No
GO to AF7.
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AF7 CHECK THE THIRD ROW POWER SEAT RELAY FOR VOLTAGE
- Verify the vehicle is in PARK and the liftgate is open.
- Verify the courtesy lights are on. If needed, close and open any door on the vehicle.
- Measure the voltage between third row power seat relay socket pin 2, circuit CLN09 (YE/GN) and ground.
- Is the voltage greater than 10 volts?
Yes
REPAIR circuit GD120 (BK/GN) for an open. TEST the system for normal operation.
No
REPAIR circuit CLN09 (YE/GN). TEST the system for normal operation.
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AF8 CHECK THE THIRD ROW POWER SEAT RELAY FOR VOLTAGE
- Measure the voltage between third row power seat relay socket pin 5, circuit SBB33 (RD), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
GO to AF9.
No
VERIFY Battery Junction Box (BJB) fuse 33 (30A) is OK. If the fuse is OK, REPAIR the circuit. If not OK, REFER to the Wiring Diagrams to identify possible causes of the circuit short. TEST the system for normal operation. Diagrams By Number
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AF9 CHECK THE CIRCUIT BETWEEN THE PFSM AND THE THIRD ROW POWER SEAT RELAY FOR AN OPEN
- Ignition OFF.
- Measure the resistance between PFSM C4250A-8, circuit CBB18 (GY/OG), harness side and third row power seat relay socket pin 3, circuit CBB33 (WH/BN).
- Is the resistance less than 5 ohms?
Yes
INSTALL a new third row power seat relay. TEST the system for normal operation.
No
REPAIR circuit CBB18 (GY/OG)/CBB33 (WH/BN) for an open. TEST the system for normal operation.
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AF10 CHECK THE PFSM ENABLE CIRCUIT FOR A SHORT TO VOLTAGE
- Disconnect: PFSM C4250E.
- To access the PFSM, refer to the appropriate steps in Power-Fold Seat Module (PFSM) Power-Fold Seat Module (PFSM).
- Disconnect: SJB C2280C.
- Measure the voltage between PFSM C4250E-4, circuit CPS58 (WH/BN), harness side and ground.
- Is any voltage present?
Yes
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
No
GO to AF21.
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AF11 CHECK THE PFSM ENABLE CIRCUIT FOR AN OPEN AND SHORT TO GROUND
- Ignition OFF.
- Disconnect: PFSM C4250E.
- To access the PFSM, refer to the appropriate steps in Power-Fold Seat Module (PFSM) Power-Fold Seat Module (PFSM).
- Disconnect: SJB C2280C.
- Measure the resistance between:
- PFSM C4250E-4, circuit CPS58 (WH/BN), harness side and SJB C2280C-24, circuit CPS58 (WH/BN), harness side.
- PFSM C4250E-4, circuit CPS58 (WH/BN), harness side and ground.
- Is the resistance less than 5 ohms between C4250E and C2280C, and greater than 10,000 ohms between C4250E and ground?
Yes
GO to AF21.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
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AF12 CHECK THE PFSM ENABLE CIRCUIT FOR VOLTAGE
- Disconnect: PFSM C4250E.
- To access the PFSM, refer to the appropriate steps in Power-Fold Seat Module (PFSM) Power-Fold Seat Module (PFSM).
- Verify the vehicle is in PARK and the liftgate is open.
- Verify the courtesy lights are on. If needed, close and open any door on the vehicle.
- Measure the voltage between PFSM C4250E-4, circuit CPS58 (WH/BN), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
GO to AF13.
No
GO to AF21.
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AF13 CHECK FOR VOLTAGE TO THE SEAT CONTROL SWITCH
- Connect: PFSM C4250A (if previously disconnected).
- Remove the third row seat control switch but do not disconnect the electrical connector at this time. Refer to Seat Control Switch - Third Row Seat Control Switch - Third Row.
- Verify the vehicle is in PARK and the liftgate is open.
- Verify the courtesy lights are on. If needed, close and open any door on the vehicle.
- With all the switch buttons at rest and seat select set to BOTH, measure voltage between the seat control switch and ground by back-probing switch connector pins as indicated in the following table:
- Do the voltages agree with the expected voltages in the table?
Yes
GO to AF18.
No
GO to AF14.
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AF14 CHECK CIRCUITS FOR VOLTAGE WITH THE SEAT CONTROL SWITCH DISCONNECTED
- Disconnect: Seat Control Switch C4179.
- Verify the vehicle is in PARK and the liftgate is open.
- Verify the courtesy lights are on. If needed, close and open any door on the vehicle.
- Measure the voltage between seat control switch C4179, harness side and ground using the following table:
- Do the voltages agree with the expected voltages in the table?
Yes
INSTALL a new seat control switch. REFER to Seat Control Switch - Third Row Seat Control Switch - Third Row. TEST the system for normal operation.
No
GO to AF15.
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AF15 CHECK THE SEAT CONTROL SWITCH CIRCUITS FOR A SHORT TO VOLTAGE
- Disconnect: PFSM C4250C.
- Disconnect: PFSM C4250D.
- Measure the voltage between seat control switch C4179, harness side and ground using the following table:
- Is any voltage present?
Yes
REPAIR the circuit(s). TEST the system for normal operation.
No
GO to AF16.
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AF16 CHECK THE SEAT CONTROL SWITCH CIRCUITS FOR AN OPEN OR SHORT TO GROUND
- Measure the resistance between seat control switch circuits, harness side and PFSM, harness side; and between seat control switch circuits, harness side and ground using the following table:
- Are the resistances less than 5 ohms between C4179 and PFSM and greater than 10,000 ohms between the C4179 and ground?
Yes
GO to AF17.
No
REPAIR the affected circuit(s). TEST the system for normal operation.
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AF17 CHECK THE SEAT CONTROL SWITCH CIRCUITS FOR A SHORT TOGETHER
- Measure the resistance between seat control switch C4179 circuits, harness side, using the following table:
- Are the resistances greater than 10,000 ohms?
Yes
GO to AF22.
No
REPAIR the affected circuit(s). TEST the system for normal operation.
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AF18 CHECK THE VOLTAGE AT THE SEAT CONTROL SWITCH CIRCUITS
NOTE: C4250E must be disconnected or inaccurate meter measurements may be taken.
- Disconnect: PFSM C4250E.
- To access the PFSM, refer to the appropriate steps in Power-Fold Seat Module (PFSM) Power-Fold Seat Module (PFSM).
- Verify the vehicle is in PARK and the liftgate is open.
- Verify the courtesy lights are on. If needed, close and open any door on the vehicle.
- Measure the voltage between seat control switch C4179 and ground by back-probing switch connector pins and pressing the switch buttons as indicated in the following table:
- Do the measured voltages agree with the table?
Yes
GO to AF22.
No
INSTALL a new seat control switch. REFER to Seat Control Switch - Third Row Seat Control Switch - Third Row. TEST the system for normal operation.
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AF19 CHECK THE SEAT CONTROL SWITCH CIRCUITS FOR A SHORT TOGETHER
- Disconnect: Seat Control Switch C4179.
- Disconnect: PFSM C4250C.
- Disconnect: PFSM C4250D.
- Using the following table, measure the resistance between the seat control switch C4179 pins indicated, harness side:
- Are the resistances greater than 10,000 ohms?
Yes
GO to AF20.
No
REPAIR the affected circuit(s). TEST the system for normal operation.
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AF20 CHECK THE LATCH SWITCH AND LATCH MOTOR RETURN CIRCUITS FOR AN OPEN
- Gain access to the LH latch switch connector. Refer to the appropriate steps in Seat Latch - Third Row, Power Seat Latch - Third Row, Power.
- Disconnect: Left Seat Latch Switch C4241.
- Disconnect: Left Seat Latch Motor C4243.
- Disconnect: PFSM C4250A.
- Measure the resistance between:
- PFSM C4250A-12, circuit CPS51 (VT/GY), harness side and left seat latch switch C4241-2, circuit CPS51 (VT/GY), harness side.
- PFSM C4250A-6, circuit CPS04 (YE/OG), harness side and left seat latch motor C4243-2, circuit CPS04 (YE/OG), harness side.
- Are the resistances less than 5 ohms?
Yes
GO to AF22.
No
REPAIR the affected circuit(s). TEST the system for normal operation.
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AF21 CHECK SJB CONNECTORS AND PINS FOR DAMAGE AND RETEST THE SYSTEM
- Inspect SJB C2280C for corrosion and pushed out or damaged pins and repair as necessary.
- Connect: SJB C2280C.
- Connect: PFSM C4250E.
- Operate the seats and determine if the concern is still present.
- Is the concern still present?
Yes
INSTALL a new SJB. REFER to Multifunction Electronic Modules Service and Repair. TEST the system for normal operation.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.
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AF22 CHECK PFSM CONNECTORS AND PINS FOR DAMAGE AND RETEST THE SYSTEM
- Inspect the PFSM connectors for corrosion and pushed out or damaged pins and repair as necessary.
- Reconnect all the PFSM connectors.
- Connect: Left Seat Latch Switch C4241.
- Connect: Left Seat Latch Motor C4243.
- Operate the seats and determine if the concern is still present.
- Is the concern still present?
Yes
INSTALL a new PFSM. Refer to Power-Fold Seat Module (PFSM) Power-Fold Seat Module (PFSM). TEST the system for normal operation.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.
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