Electrical testing of idling speed stabilisation valve — AUDI
Electrical testing of idling speed stabilisation valve on Audi: factory workshop procedure for engines ABZ, AEW, AHC, AKG.
Workshop procedure for AUDI — the factory write-up, straight from real workshop data.
📐 18 workshop diagrams for ABZ
Real factory drawings for this job — timing marks, bolt locations and routing. Locked in the free view.
📋 Procedure
AEW AHC AKG AKJ AKH
Detach connector from valve -N71.
Measure resistance between valve contacts with hand multimeter V.A.G 1526.
Specified value: 7.0 - 11.0 ohms
If specified value is not reached, renew idling speed stabilisation valve -N71.
Note:
At room temperature the resistance is in the lower tolerance range; when the engine is at operating temperature, it is in the upper range.
Mechanical testing of idling speed stabilisation valve -N71
Unscrew valve -N71 from engine (wire remains connected).
Check rotary valve for scoring (visual check).
Note:
Do not move rotary valve with a screwdriver or other tool to test ease of movement.
Initiate final control diagnosis and actuate idling speed stabilisation valve=>Page
01-79
.
Test whether rotary valve moves freely from stop to stop.
If scoring is impairing its movement (catching or not running to stops), renew valve.
If valve does not respond in final control diagnosis, check activation=>Page
24-57
.
Testing activation of idling speed stabilisation valve -N71
Detach connector from idling speed stabilisation valve -N71 and connect diode test lamp V.A.G 1527 between contacts 1 and 2 of connector.
Initiate final control diagnosis and actuate idling speed stabilisation valve=>Page
01-79
.
The diode test lamp should flash.
Notes:
The diode test lamp does not go out completely, it just becomes brighter or dimmer.
The idling speed stabilisation valve final control diagnosis is aborted after one minute. To repeat the test, briefly switch off the ignition and initiate final control diagnosis again.
If the diode test lamp does not flash:
Connect test box V.A.G 1598/19 to engine control unit wiring harness=>Page
24-15
.
Check wiring connection between contact 1 of valve -N71 connector and socket D5 on test box, and between contact 2 and socket D1 for break or short circuit.
=> Current Flow Diagrams, Electrical Fault-Finding and Fitting Locations binder
If wiring is OK, and valve is not actuated, renew engine control unit=>Page
24-16
.
TorqFix answers live for your specific car — tell it the engine code and it serves the matching sequence, torque figures and wiring for that exact variant.
Ask about my car →Other AUDI procedures
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Who makes these pages, and how
TorqFix was built by a mechanic — after a 2,700 km drive with five roadside repairs that no diagnostic tool could explain.
The figures on this page come from manufacturer workshop documentation and are shown as they are. The page is assembled automatically from that data — it is not written by an AI. The AI works in the chat, where it answers for your specific car. It writes nothing here.
Variants of the same model differ. Cross-check torque against the factory manual for your engine before final tightening.
Seen a figure that does not match your manual? Write to us — we correct it and note when. support@torqfix.com
The story behind TorqFix →Workshop data on this page last updated 20 Sep 2026.