Does anyone know how to test the vacume motor located under the rear seat of a 1987 300E? I am getting no response from it. I understand that the three pin terminal activates the motor ... (1 wire each for trunk, passenger and driver's door) and the two pin terminal powers the motor (poistive and ground).

Smiles.

[Edited by ejsharp on 04-28-2001 at 05:25 PM]

The ground and power are permanent and I believe that the front doors and trunk lid lock send a ground signal to activate the pump.

greetingz,

Thanks MB... I had suspected that a ground activated or triggered (through circuit board) the constant hot wire and ground that operated the pump.

Gilly is send me a wiring diagram and knowing to lookout for a ground signal is very helpful.

Thanks.