LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Volkswagen >> 1996 >> Passat GLS, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 7 (Engine Controls - System/Component Tests) >> Idle Control System >> Idle Air Control (IAC) Valve
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Idle Air Control (IAC) Valve

WARNING: This page is about a different car, the 1995 Volkswagen Passat. However, it is still accessible from the selected car via links, so may be relevant.
  1. Connect Scan Tester (VAG 1551) to Data Link Connectors (DLC) located in center console, in front of shift lever. With scan tester in OUTPUT DIAGNOSTIC TEST MODE, test IAC valve. See the TESTS W/CODES article.
  2. To check IAC valve triggering circuit, turn ignition off. Disconnect wiring harness connector from idle air control valve. Connect LED Tester (US 1115) to wiring harness connector terminals No. 1 and 2.
  3. Turn ignition on. Perform OUTPUT DIAGNOSTIC TEST MODE until IAC valve is triggered. LED tester must flash. If LED tester does not flash, check IAC valve circuit.
  4. If LED tester flashes, disconnect wiring harness connector from idle air control valve. Using Test Leads from Adapter Kit (VW 1594), connect DVOM to IAC valve terminals No. 1 and 2. IAC valve resistance must be 10-20 ohms. If resistance is incorrect, replace IAC valve.
scientia non olet · About LEMON Manuals