Checking wires to Engine Control Module (ECM)

2002 Volkswagen Golf GLS, 2.0 K, StandardSECTION Checking wires to Engine Control Module (ECM)
WARNING: This page does not describe the selected car, but rather 14 other vehicles, including the 2005 Volkswagen GTI, 2004 Volkswagen R32, 2004 Volkswagen Jetta, 2004 Volkswagen GTI, and 2003 Volkswagen Jetta. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: 5-Pin Connector Terminals 1 & 5
GW00001239Courtesy of VOLKSWAGEN UNITED STATES, INC.
  • Check wires between test box and 5-pin connector for open circuit according to wiring diagram.

Terminal 2+socket 102

Terminal 3 + socket 94

Terminal 4 + socket 103

Wire resistance: max. 1.5 Ω

  • Also check wires for short circuit to each other.

Specified value: ∞ Ω

If no malfunctions are found in the wires and there was voltage between terminal 1 + 5:

Checking secondary resistances 

Fig 2: Checking Secondary Resistances At Terminal 4 Between Cylinders
GW00001240Courtesy of VOLKSWAGEN UNITED STATES, INC.
  • Check secondary resistances at terminal 4 between

Cyl. 1 + Cyl. 6,

Cyl. 3 + Cyl. 4,

Cyl. 2 + Cyl. 5.

Specified value: 3.6 to 4.4 k Ω

If specified values are not obtained:

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.

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.