Multiplex Control System

Multiplex Control Unit Input Test (cont'd)

 22-278  

  1. With the connectors still disconnected, make these input tests at the connector.
Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
J4 BLK Under all conditions Check for continuity to ground: There should be continuity.

  • Poor ground (G301)
  • An open in the wire
Y6 BLK Under all conditions Check for continuity to ground:

There should be continuity.
  • Poor ground (G501)
  • An open in the wire
Y1 BLK Under all conditions Check for continuity to ground:

There should be continuity.
  • Poor ground (G502)
  • An open in the wire
J2 WHT/RED Under all conditions Check for voltage to ground:

There should be battery voltage.
  • Blown No. 9 (10A) fuse in the under-hood fuse/relay box
  • An open in the wire
  1. Reconnect the connectors to the under - dash fuse/relay box and make sure these input tests at the appropriate connectors on the under - dash fuse/relay box.
Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
Q3 GRN Driver's door open Check for voltage to ground:

There should be 1 V or less.
  • Faulty driver's door switch
  • An open in the wire
Driver's door closed Check for voltage to ground:

There should be 5 V or more.
  • Faulty driver's door switch
  • Short to ground
Q4 LT GRN/RED Front passenger's door open Check for voltage to ground:

There should be 1 V or less.
  • Faulty front passenger's door switch
  • An open in the wire
Front passenger's door closed Check for voltage to ground:

There should be 5 V or more.
  • Faulty front passenger's door switch
  • Short to ground
Q2 GRN/WHT Left or right rear door open Check for voltage to ground:

There should be 1 V or less.
  • Faulty rear door switch
  • An open in the wire
Left or right rear door closed Check for voltage to ground:

There should be 5 V or more.
  • Faulty rear door switch
  • Short to ground
Q8

·

C8

·

F1

 GRN/ORN

·

GRN/RED

 Parking brake lever up Check for voltage to ground:

There should be 1 V or less.
  • Faulty parking brake switch
  • An open in the wire
Parking brake lever up Check for voltage to ground:

There should be 5 V or more.
  • Faulty parking brake switch
  • Short to ground
Q5 BLU/RED Ignition switch ON (II) driver's seat belt unbuckled. Check for voltage to ground:

There should be 1 V or less.
  • Faulty driver's seat belt switch
  • Poor ground (G551)
  • An open in the wire
Q6 BLU/RED
P18 RED Trunk lid [tailgate] open Check for voltage to ground:

There should be 1 V or less.
  • Faulty trunk[tailgate]latch switch
  • Poor ground (G601)
  • An open in the wire
Trunk lid closed Check for voltage to ground:

There should be 5 V or more.
  • Faulty trunk[tailgate]latch switch
  • Short to ground
X5 RED/WHT Ignition key is in the ignition switch Check for voltage to ground:

There should be 1 V or less.
  • Faulty ignition key switch
  • Poor ground (G401)
  • An open in the wire
Ignition key is out of the ignition switch Check for voltage to ground:

There should be 5 V or more.
  • Faulty ignition key switch
  • Short to ground

[ ]: 5-door