Circuit Description

Power to both driver and passenger seats, as well as power door locks, rear blower, and front fog lamps (if so equipped), is provided by the A3 circuit through a 40 amp MAXI-fuse in the Power Distribution Center (PDC) under the hood. If all of these devices are nonfunctional, replace the MAXI-fuse. If the new MAXI-fuse blows immediately, correct the wiring short to Ground that could be on any of those aforementioned loads before proceeding further.

Once the power is back ON, if the power seats still do not work, check the 30 amp circuit breaker that is located in the driver's seat wiring harness approximately 10 inches from the 4-way connector. The power feed circuit to the 30 amp circuit breaker is 14 ga. A3 RD/WT.

Following the 30 amp circuit breaker is a 14 ga. wire designated as F35 RD that provides power into the MSMM and is double crimped with a 14 ga. F35A RD that provides power to the passenger seat through the 4-way connector.

If the power door locks, rear blower, and front fog lamps (if so equipped) are functional and the seats are both nonfunctional, repair/replace the open wiring and/or circuit breaker in the driver's seat harness to correct the condition.

Ensure that the 12 ga. ground wire Z1 BK from the electrical distribution wiring ground splice into the 4-way connector is providing ground. The Z1 BK is double crimped at the seat harness side of the 4-way connector taking a 14 ga. Z1 BK into the 10-way connector (cavity 7) 14 ga. This double crimp carries a 20 ga. Z1A BK to cavity 3 of the power seat switch 10-way. If the passenger power seat is functional, and the driver's seat is nonfunctional examine the circuit F35 RD from the double crimped circuit breaker connector into the 10-way connector cavity 8 of the control module for continuity. Repair or replace as necessary. If the driver's seat is still nonfunctional, use a multi-function meter to check the P9 RD 20 ga. circuit from the control module 21-way connector (cavity 11) to the power seat switch 10-way connector (cavity 5). This is a low current battery feed from the control module that will not illuminate a test lamp.

During shipping of the vehicle, an M1 circuit 10 amp fuse (labeled IOD) is temporarily removed from the PDC in the engine compartment to eliminate unnecessary battery depletion. However, this fused circuit being open (that feeds through the electrical distribution wiring to cavity 16 of the 25-way connector) will not stop manual seat actuations from taking place (only recall mode requests) during shipping.
1. If the memory seat/mirror module does not respond with a relay click to any seat switch input (as well as the desired motion) when actuated, proceed with the following analysis:
- Verify power ON F35 and ground Z1 into the system as indicated above.
- Verify all connectors are mated with the MSMM.
- Place the vehicle gear shift lever in any position except PARK (causes the Memory Seat/Mirror Module to wake-up and provide a position sense voltage to the seat motor potentiometers and the mirror rheostat(s). This voltage can be checked at the appropriate cavities of the 21 and 25-way connectors.
- Verify the switch connector is mated with the seat switch on the inside of the outboard side-shield.
- Verify battery voltage at the P9 circuit referenced to the Z1A ground reference (cavity 1) of the seat switch. If P9 low current battery is not available coming from the module, replace the MSMM.
- If P9 low current battery is present at (cavity 5) referenced to ground Z1 (cavity 1) of the seat switch, verify the presence of the P9 voltage at the switch outputs. If there is no output voltage from the switch, replace the switch.
- If P9 voltage is present at the output of the switch, but there is no reaction from the memory seat/mirror module, verify that the P9 voltage is present at the appropriate 21-way connector pins into the module. If the P9 voltage is not present at the 21-way connector, repair or replace the seat wiring harness. If the verification check of the seat wiring harness is correct, replace the control module.
2. If the control module does not respond with a relay click to a specific seat switch when actuated, verify the continuity of the particular circuit between the seat switch and the MSMM. If the P9 voltage is present at the correct input of the 21-way connector of the module when the switch is actuated, but there is no response by the module, replace the MSMM.
3. If the MSMM responds with a relay click when a seat switch is actuated for a given direction, but there is no reaction from a seat or recliner motor relating to that switch input, disconnect the 10-way connector from the control module. Jumper the battery and ground from cavities 8 and 7 of the seat harness 10-way connector to the proper cavities for the seat or recliner motor in question and direction of travel desired. If the motor operates, replace the control module, If the motor does not operate, verify continuity of the wiring into the motor 2-way connector. Repair or replace the wiring as necessary. If the wiring has continuity, and the motor will not operate when fed directly, replace the track assembly, since the motor/transmission combinations are not designed to be serviced on an individual basis.