Pinpoint Test F: 4-Way Lumbar Down Tests

TEST CONDITIONS 

DETAILS/RESULTS/ACTIONS 

1. F1: LUMBAR DOWN TEST 1 
   NOTE:

   • Circuit reference - LUMBAR UP/GND -
   • The 4-way lumbar down circuit current specification is 1.55A ± 10%.
   1. Connect an inductive ammeter to the seat switchpack power circuit
   2. Set the ignition to on
   3. Operate the seat switchpack lumbar down switch

   Is the measured current less than specification?

   • Yes  : GO to F2.
   • No  : Check the lumbar/bolster pump hose and the lumbar air cell hoses for blockages/leaks
2. F2: LUMBAR DOWN TEST 2 
   NOTE: Do not disconnect the electrical connector during this step; the seat switchpack is removed for access to the wiring harness only.
   1. Refer to the relevant section of the service information and remove the seat switchpack
   2. Set a multimeter to measure voltage
   3. Using the multimeter, measure and record the battery voltage (reference voltage)
      NOTE: Circuit reference - LUMBAR DWN/GND -
   4. Connect the multimeter across the seat switchpack lumbar down terminal and the ground terminal
   5. Set the ignition to on
   6. Operate the seat switchpack lumbar down switch

   Is the measured voltage less than battery voltage?

   • Yes  : GO to Pinpoint Test A .
   • No  : Refer to the applicable System Wiring Diagram(s) and check the lumbar down circuit for short circuit to ground, short circuit to power, open circuit, high resistance
     NOTE: The battery support unit must be connected during this test to ensure that the power supply is stable.