Test 1: Pneumatic System Equipment Control Module
WARNING: This page is about a different car, the 2000 Mercedes-Benz SLK230 and 1999 Mercedes-Benz SLK230. However, it is still accessible from the selected car via links, so may be relevant.
Connect harness adapter and breakout box to Pneumatic System Equipment (PSE) control module. Measure voltage between terminals No. 3 and 4, and between terminals No. 2 and 3 at breakout box. Battery voltage should exist. If battery voltage is as specified, test is complete. If battery voltage does not exist, check wiring. See WIRING DIAGRAMS .