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Test F: Power Lumbar Inoperative

CAUTION: On models equipped with side air bags, a Side Air Bag Simulator (418-133) must be connected to side air bag and seat belt pretensioner floor connectors before diagnosing or repairing power seats.
  1. Turn ignition switch to LOCK position. On models equipped with side air bags, deactivate system before diagnosing. See appropriate AIR BAG RESTRAINT SYSTEMS article. Ensure to disconnect any auxiliary power supplies. Press suspect lumbar seat control switch to INFLATE position. If lumbar pump motor does not run, go to next step. If lumbar pump motor runs, go to step  7 .
  2. Operate power seat control switch on seat with inoperative power lumbar system. If power seat operates, go to next step. If driver's power seat does not operate, perform TEST A: DRIVER'S POWER SEAT INOPERATIVE  . If passenger's power seat does not operate, perform TEST B: PASSENGER'S POWER SEAT INOPERATIVE  .
  3. Disconnect suspect lumbar seat control switch 2-pin harness connector, located under appropriate seat. Measure voltage between ground and suspect lumbar seat control switch harness connector (Dark Green wire terminal on driver's seat or Black/White wire terminal on passenger's seat). If voltage is 10 volts or more, go to next step. If voltage is less than 10 volts, repair open in appropriate wire. See WIRING DIAGRAMS  .
  4. Disconnect suspect lumbar motor 2-pin harness connector, located in appropriate seat. Measure resistance between ground and lumbar motor harness connector Black wire terminal. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in Black wire between suspect lumbar motor and ground point. Ground point is located behind left side kick panel.
  5. Connect lumbar seat control switch harness connector. Measure voltage between ground and suspect lumbar motor harness connector Red Wire terminal. Press suspect lumbar seat control switch to INFLATE position. If voltage is less than 10 volts, go to next step. If voltage is 10 volts or more, replace lumbar motor. See LUMBAR MOTOR  under REMOVAL & INSTALLATION.
  6. Disconnect suspect lumbar seat control switch 2-pin harness connector, located under appropriate seat. Measure resistance of Red wire between lumbar seat control switch harness connector terminal and lumbar motor harness connector terminal. If resistance is less than 5 ohms, replace lumbar seat control switch. See LUMBAR SEAT CONTROL SWITCH  under REMOVAL & INSTALLATION. If resistance is 5 ohms or more, repair open in Red wire. See WIRING DIAGRAMS  .
  7. Press suspect lumbar seat control switch to INFLATE position and observe seat back lumbar adjusting pad. If lumbar adjusting pad does not inflate, go to next step. If lumbar adjusting pad inflates, go to step  11 .
  8. Visually inspect lumbar adjusting pad. If lumbar adjusting pad is not damaged, go to next step. If lumbar adjusting pad is damaged, replace lumbar adjusting pad.
  9. Disconnect lumbar adjusting hose from lumbar motor. Press suspect lumbar seat control switch to INFLATE position while feeling for air at motor hose connection. If air is felt at lumbar motor hose connection, go to next step. If air is not felt at lumbar motor hose connection, replace lumbar motor. See LUMBAR MOTOR  under REMOVAL & INSTALLATION.
  10. Connect hose to lumbar motor. Disconnect lumbar adjusting hose from lumbar seat control switch. Press suspect lumbar seat control switch to INFLATE position. If air can be felt at lumbar adjusting hose, go to next step. If air can not be felt at lumbar adjusting hose, replace lumbar adjusting hose.
  11. Connect lumbar adjusting hose to lumbar seat control switch, if previously disconnected. Disconnect lumbar adjusting hose at lumbar adjusting pad. Install in-line pressure gauge on lumbar adjusting hose. Press suspect lumbar seat control switch to INFLATE position until gauge reads 5 psi (34.47 kPa). Wait 3 hours, then read gauge. If pressure reading is less than 4.7 psi (32.41 kPa), go to next step. If pressure reading is 4.7 psi (32.41 kPa) or more, system is operating correctly.
  12. Remove in-line pressure gauge. Use hand pump and inflate lumbar adjusting pad to 5 psi (34.47 kPa). Wait 3 hours, then read gauge. If pressure reading is 4.7 psi (34.47 kPa) or more, replace lumbar seat control switch. See LUMBAR SEAT CONTROL SWITCH  under REMOVAL & INSTALLATION. If pressure reading is less than 4.7 psi (34.47 kPa), replace lumbar adjusting pad.
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