SEAT Workshop Service and Repair Manuals

Voltage supply relay for the engine control unit -J271-: verification

Special tools and workshop equipment required

t	Hand multimeter -V.A.G 1526A- oder multimeter -V.A.G 1715-

t	Auxiliary measurement tool set -V.A.G 1594A- or -V.A.G 1594C-

t	Double connection engine testing unit -V.A.G 1598/31-

t	Current flow diagrams

Note! t  For vehicles with the engine identification BBX, the verification is done using -VAS 5051- → VAS 5051; Vehicle self-diagnosis. t  The current supply relay -J271- supplies current to the engine coil final power stage as well as the engine control unit through the contact 121 for AZL engines and contact 27 for BBX engines. Test conditions l  The fuses must be OK. l  Battery voltage at least 11.5 V l  Hall sender -G40-, OK; verification → Chapter l  Engine speed sender -G28-,OK: verification → Chapter Verification process

–  Remove the engine cover -arrows-.

–  Disconnect the four pin connector -1- from the final power stage for the engine coils -2-.

–  Measure the voltage with the multimeter and the auxiliary cables of -V.A.G 1594 A- or -V.A.G 1594 C- as follows:

Connector, contact	Connector, contact
2	4

–  Turn the ignition on. Specification: about the battery voltage. If the ideal value is not measured: –  Switch ignition off. –  Remove the object tray from the drivers side: → Bodywork - mounting work, interiors; Rep. Gr.68.

–  Test the connection between the connector and the relay carrier:

Connector, contact	Relay carrier (relay position 10), connected
4	6

If the wiring is OK: –  Test the voltage supply for the Motronic current supply relay -J271- → Chapter. –  Test the operation of the Motronic current supply relay -J271- → Chapter.