1994 Mercedes Benz S320FACTORY OEM SERVICE PROCEDURE

Diagnostic Trouble Code Memory (Section 11)

NOTE: DTC readout using the impulse counter scan tool or via the LED pushbutton switch, has been eliminated. During the DTC readout, the CHECK ENGINE MIL, stays on continuously.

Diagnostic module (OBD II< N59/1) uses 2 different plug connectors for DTC readout:

  • 16-pin OBD II connector (X11/22). See Figure.
  • 38-pin data link connector (X11/4). See Figure.

In case of DTC P0131 and P0133, the exact cause of the fault in oxygen sensor 1 (O2S 1) can be read via MODE 5 with the generic scan tool. To do so, the following codes must be entered in the generic scan tool:

  1. DTC P0131

    Code JD 4A HEX

  2. DTC P0133

    Code JD 7E HEX

Chapter Navigation
Return to Chapter: Self-Diagnostic System
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.