2011 Chevrolet CapriceFACTORY OEM SERVICE PROCEDURE

Circuit/System Testing

  1. Ignition OFF, disconnect the SIM harness connector.
  2. Test for less than 1 ohm between the module ground circuits and ground.
    • If greater than 1 ohm, repair the ground circuit for an open/high resistance.
  3. Ignition ON, verify that a test lamp illuminates between all battery positive voltage circuits and ground.
    • If the test lamp does not illuminate, repair the circuit for a short to ground or an open/high resistance. If the circuit fuse is open, also test the positive voltage outputs of the module for a short to ground. If the circuits test normal, replace the SIM.
  4. Verify that a test lamp illuminates between all ignition voltage circuits and ground.
    • If the test lamp does not illuminate, repair the circuit for a short to ground or an open/high resistance. If the circuit fuse is open, also test the positive voltage outputs of the SIM for a short to ground. If the circuits test normal, replace the SIM.
  5. Ignition ON, verify that a test lamp illuminates between the serial data communication enable circuit OR the accessory wakeup serial data circuit and ground.
    • If the test lamp does not illuminate, repair the circuit for an open/high resistance. If the circuits test normal, replace the BCM.
  6. Test for less than 1 ohm in the low speed GMLAN serial data circuit between the SIM and the module that displays the DTC.
    • If greater than 1 ohm, test the low speed GMLAN serial data circuit for open/high resistance.
  7. If all circuits test normal, replace the SIM.
Factory Service Tools

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.

Shop Manual-Ready ToolsCompare Repair QuoteQuote Shield Pro

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

Rather have a pro handle this?

A certified mobile mechanic comes to your home or office. They bring the tools, you stay comfortable. No tow truck, no waiting room, no surprises.

Comes to youSame-day available12-month warranty
Get a Free Quote

No obligation. See pricing before you book.