Test B: Lumbar Support Inoperative
- Review power lumbar support operation. See DESCRIPTION & OPERATION
. Go to next step.
- Using lumbar adjuster switch, attempt to operate driver's and passenger's lumbar and bolster bladders. If power lumbar bladders do not deflate and inflate properly, go to next step. If power lumbar bladders deflate and inflate properly, inspect for intermittents. See TROUBLE SHOOTING
.
- If both driver's and passenger's power lumbar support inoperative, go to next step. If either driver's or passenger's power lumber support is inoperative, go to step 6
.
- Disconnect power seat cushion air control module 6-pin harness connector C1. Power seat cushion air control module is located below driver's seat. See Figure
. Connect a test light between ground and power seat cushion air control module harness connector C1 terminal "A" (Orange wire). See Fig 1
. If test light illuminates, go to next step. If test light does not illuminate, go to step 7
.
- Disconnect power seat cushion air control module 4-pin harness connector C2. Connect a test light between power seat cushion air control module harness connector C1 terminal "A" (Orange wire) and power seat cushion air control module harness connector C2 terminal "D" (Black wire). See Fig 1
. If test light illuminates, go to next step. If test light does not illuminate, go to step 8
.
- Disconnect power seat cushion air control module harness connectors C1 (6-pin) and C2 (4-pin). Power seat cushion air control module is located below driver's seat. See Figure
. Connect a test light between ground and power seat cushion air control module harness connector terminal for suspect switch signal circuit. See WIRING DIAGRAMS
. Press suspect lumbar adjuster switch. If test light does not illuminate, go to step 9
. If test light illuminates, go to step 11
.
- Repair open, high resistance or short to ground in Orange wire between driver's lumbar adjuster switch and instrument panel fuse block. Instrument panel fuse block is located behind left side of instrument panel. Go to step 12
.
- Repair open or high resistance in Black wire between power seat cushion air control module and ground. Ground point is located bolted to left rocker panel at floor pan bar. Go to step 12
.
- Inspect switch signal circuit for an open, high resistance or short to ground between ground and suspect lumber adjuster switch harness connector. See WIRING DIAGRAMS
. If an open, high resistance or short to ground is not found, go to next step. If an open, high resistance or short to ground is found, repair as necessary then go to step 12
.
- Replace suspect lumbar adjuster switch, then go to step 12
.
- Replace power seat cushion air control module, then go to next step.
- Operate system to verify repair. If system, is not operating properly, repeat test beginning at step 3
.
Courtesy of GENERAL MOTORS CORP.