Checking Motronic current supply relay J271 on vehicles with engine code letters “BES” — AUDI
Checking Motronic current supply relay J271 on vehicles with engine code letters “BES” on Audi: factory workshop procedure for engines AJK, ARE, AZA.
Workshop procedure for AUDI — the factory write-up, straight from real workshop data.
📐 20 workshop diagrams for AJK
Real factory drawings for this job — timing marks, bolt locations and routing. Locked in the free view.
📋 Procedure
Checking
Motronic current supply relay
J271
on vehicles with engine code letters
“BES”
The
Motronic current supply relay
J271
provides voltage for the ignition coils/output stages and the engine control unit at contact 3.
Special tools and workshop equipment required
Hand-held multimeter
V.A.G 1526 A
Auxiliary measuring set
V.A.G 1594 A
Adapter cable, 121-pin
V.A.G 1598/31
(test box)
Procedure
Ignition off.
Disconnect 4-pin connectors from ignition coils.
Note
For further checking, multimeter is attached to connector of one ignition coil.
Connect multimeter (voltage measuring range) between contact
1
of connector and earth.
Switch on ignition.
Specification: approx. battery voltage
Switch off ignition.
If specification is not obtained:
Detach rubber seal of plenum chamber cover in direction of arrow.
Detach plenum chamber cover
1
towards the front.
Remove cover for electronics box in plenum chamber
arrows
.
Use screwdriver to pry off retaining strap for engine control unit
arrow
and lay control unit aside.
Detach current supply relay
3
.
Check for open circuit in wiring from 3-position relay carrier (in plenum chamber electronics box), position 3, contact
8
to contact 1 of connector at ignition coil via fuse.
Repair wiring connection if necessary.
If the wiring is OK:
Check voltage supply and activation of current supply relay as described in the following.
Checking voltage supply
Current supply relay detached.
First connect multimeter (voltage measuring range) between relay carrier contact
1
and earth and then between contact
2
and earth.
Specification: approx. battery voltage in each case.
If specification is not obtained:
Refer to current flow diagram and check for open circuit in wiring from battery plus (terminal 30) to current supply relay.
Checking activation
Current supply relay detached.
Connect multimeter (voltage measuring range) between relay carrier, contact
4
and battery plus.
Switch on ignition.
Specification: approx. battery voltage
If specification is not obtained:
Switch off ignition.
Connect
adapter cable, 121-pin
V.A.G 1598/31
(test box) to wiring harness for engine control unit, but do not connect the engine control unit itself
Chapter
.
Check for open circuit and short to positive or earth in the following wiring:
3-position relay carrier in electronics box in plenum chamber, position 3
Contact
V.A.G 1598/31
Socket
4
23
Specification: Wire resistance: max. 1.5 Ω.
Repair wiring connection if necessary.
If no fault is found:
Renew
Motronic current supply relay
J271
.
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
- Removing and installing exhaust temperature sender 1G235
- Removing and installing fuel tank with attachments - Vehicles with 8-cylinder engine except for A6 allroad
- Checking by-pass air cut-off valve for central idling speed N8
- Removing and installing fuel delivery unit until approx. 11.98
- Checking fuel pump relay J17 and activation
- Removing and installing toothed belt – Audi · 56 torque figures
- Removing engine – Audi A8 D3 · 41 torque figures
- Removing camshaft timing chain from camshafts – Audi A6/A7 C7 · 38 torque figures
- Installing engine – Audi A8 D4 · 36 torque figures
- Removing and installing camshaft timing chain · 29 torque figures
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.