Mercedes-Benz R170 SLK-Class Comfort Module Central Locking PSE Pump A1708000848 - Used Original Parts

Diagnosis and Common Symptoms

From the technician's bench, the PSE (Pneumatic System Equipment) pump is the heart of the R170's convenience features. Failure is not a matter of 'if', but 'when', typically presenting as a complete loss of central locking via the remote fob and the interior switch. You'll press the button and hear nothing but silence.

The primary cause is often internal motor failure or a compromised circuit board, frequently due to moisture ingress in the trunk where the unit is housed. A key diagnostic symptom is a pump that runs continuously for 20-30 seconds after an unlock/lock command, attempting to build pressure in a leaking system before timing out. This constant operation inevitably leads to burnout. A proper diagnostic scan with STAR/DAS will typically show fault codes related to PSE timeout or lack of communication with the module.

Common symptoms of a failing PSE pump include:

• Central locking is inoperative (doors, trunk, fuel filler flap).
• The anti-theft alarm system fails to arm or disarm.
• Remote key fob functions for locking/unlocking cease to work.
• An audible hissing from a vacuum leak, followed by pump failure.

Introduction

Restore the core convenience and security functions of your SLK-Class with a reliable, cost-effective solution. This is a Genuine Mercedes-Benz PSE pump, not an aftermarket imitation. Each unit has been meticulously removed and bench-tested to ensure the motor actuates correctly and the pneumatic ports hold pressure, guaranteeing a return to full factory operation.

Product Details

• Brand: Mercedes-Benz
• Model Compatibility: R170 SLK-Class (SLK200, SLK230, SLK320, SLK32 AMG)
• Part Name: Comfort Module Central Locking PSE Pump
• Part Number: A 170 800 08 48
• Condition: Genuine Used (Tested Working)
• Notes: Before installation, inspect the foam housing and trunk well for any signs of water intrusion to prevent repeat failure. Part number on your original unit must match for guaranteed compatibility.