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Left Front Door Isolation Relay Test

  1. Remove left front door isolation relay. See Fig 1 . Use a voltmeter and check for battery voltage between relay terminal No. 5 (Orange wire) and ground. See Fig 2 . If battery voltage is not present, check wiring for an open circuit.
  2. Use a fused jumper wire and momentarily connect relay terminals No. 1 (Tan wire) and 5 (Orange wire). All doors except left front door should unlock. If not, check Tan wire for an open circuit.
  3. Connect a test light between relay terminals No. 2 (Tan wire) and 5 (Orange wire). Test light should flash once when transmitter UNLOCK button is pressed, If not, check wiring for an open or short circuit to ground, and RAC module 9-pin connector terminal "G" (Black wire) for good terminal contact.
  4. If wiring and connection are okay, replace RAC module. If all checks are okay, replace left front door isolation relay.
Fig 1: Left Front Door Isolation Relay Location
G93C40800Courtesy of GENERAL MOTORS CORP.
Fig 2: Relay Terminal ID
G93D40801Courtesy of GENERAL MOTORS CORP.
REMOTE KEYLESS ENTRY COMPONENT LOCATION

Component Location
Data Link Connector (DLC) Under Left Side Of Dashboard, To Left Of Steering Column
Door Lock Relay Under Right Side Of Dashboard
Instrument Panel Fuse Block Under Left Side Of Dashboard
Park/Neutral Position Switch On Top Of Transaxle
Remote Accessory Control (RAC) Module Under Right Side Of Dashboard