SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSCHEVROLET2006CHEVY EXPRESS G2500, VAN CARGO, 6.6 2REPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 1174 (ENGINE CONTROLS AND FUEL - 6.6L (LMM) - DTC P154B TO DTC P2693)DTC P154CCIRCUIT/SYSTEM TESTING
2006 Chevrolet Chevy Express G2500, Van Cargo, 6.6 2

Circuit/System Testing

2006 Chevrolet Chevy Express G2500, Van Cargo, 6.6 2SECTION Circuit/System Testing
WARNING: This page is about a different car, the 2007 GMC Sierra, 2007 GMC Cab & Chassis Sierra, 2007 Chevrolet Silverado, and 2007 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
IMPORTANT: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.
  1. Test the IAH current signal circuit for an open, a short to ground, or a short to voltage:
    2. IMPORTANT: Set the DMM to the 4 v DC hertz scale.
  2. With a DMM measure between command 2 circuit terminal 3 and a good ground on the harness side of the connector for 0.78-1.1 Hz.
    • If the DMM does not measure between 0.78-1.1 Hz ohms, replace the GPCM.
    3. IMPORTANT:
    • Do not install the jumper wire between 12 volts and the command circuit for more the 20 seconds.
    • Set the DMM to the 4 v AC hertz scale.
  3. Turn OFF the ignition. Install a jumper wire between the IAH harness temperature signal circuit terminal 1 and the corresponding terminal on the IAH.
  4. Install a jumper wire between the IAH harness command two circuit terminal 3 and the corresponding terminal on the IAH.
  5. Supply 12 volts to terminal 2 on the IAH.
  6. Turn ON the ignition. Measure for 1 hertz on terminal 4 at the IAH.
    • If 0.7-1.1 hertz is measured on terminal 4, replace the GPCM.
    • If 0.7-1.1 hertz is not measured on terminal 4, replace the IAH.
RENDER: 1.0x

NO RELATED

Recommended Tools & Savings

Use the Manual With the Right Hardware

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

Affiliate disclosure: We may earn a commission at no extra cost to you.

Shop Manual-Ready ToolsFree Quote CheckQuote 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.