Checking Wiring Harness - AR54.18-P-0600-01A

WARNING: This page is about a different car, the 2023 Mercedes-Benz GLC300, 2022 Mercedes-Benz GLC300, 2021 Mercedes-Benz GLC300, 2020 Mercedes-Benz GLC350e, and 2020 Mercedes-Benz GLC300. However, it is still accessible from the selected car via links, so may be relevant.

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Fig 1: Identifying Electrical Connection Kit (220 589 00 99 00)

Courtesy of MERCEDES-BENZ USA

Fig 2: Identifying 126-Pin Socket Box (129 589 00 21 00)

Courtesy of MERCEDES-BENZ USA

During tests on the supplemental restraint system control unit a corresponding test cable must be used in combination with the 126-pin socket box.

Connect electrical connection kit with test cable.
Check lines for resistance using a continuity meter as per the wiring diagram, starting at the corresponding control unit.
The resistance must be < 0.5 Ω.
Perform system test in accordance with diagnosis specifications.