Audi Workshop Service and Repair Manuals

Checking exhaust gas temperature sender

Special tools and workshop equipment required

t	Hand-held multimeter -V.A.G 1526 C- or -V.A.G 1526 A-

t	Voltage tester -V.A.G 1527 B-

t	Auxiliary measuring set -V.A.G 1594 C- or -V.A.G 1594 A-

t	Adapter cable -V.A.G 1598/31- (test box)

Procedure –  Switch off ignition. –  Unfasten screw connections -top left arrows- and detach engine cover panel -A-.

–  Unplug electrical connector on control unit of relevant exhaust gas temperature sender. 1 -  Exhaust gas temperature sender 1, bank 2 -G236- Bank 2 (black) 2 -  Exhaust gas temperature sender 1 -G235- Bank 1 (brown)   Note Disregard -arrows-. Checking voltage supply l  Fuse for exhaust gas temperature sender 1 -G235- and exhaust gas temperature sender 1, bank 2 -G236- OK → Current flow diagrams, Electrical fault finding and Fitting locations. l  Fuel pump relay -J17- OK → Current flow diagrams, Electrical fault finding and Fitting locations.   Note The voltage supply for the exhaust gas temperature sender is taken from fuel pump relay -J17-

–  Connect voltage tester -V.A.G 1527 B- between contact -3- of electrical connector for exhaust gas temperature sender 1 -G235- or exhaust gas temperature sender 1, bank 2 -G236- and engine earth. –  Operate the starter briefly. l  The LED should light up. –  Refer to current flow diagram to check for open circuit in wiring from contact -3- of connector via fuse to fuel pump relay -J17-. –  Repair wiring connection if necessary. If the LED lights up:

Checking wiring –  Connect adapter cable -V.A.G 1598/31- (test box) to connectors of wiring harness; do not connect engine control unit. Connect earth clip of test box to earth (not shown in illustration).   Caution To prevent damage to electronic components, select appropriate measuring range before connecting measuring leads and observe test requirements.

–  Check for open circuit and short to positive or earth in the following wiring:

Component	Connector Contact	Adapter cable, 121-pin -V.A.G 1598/31- Socket
Exhaust gas temperature sender 1 -G235- Bank 1 (right-side)	-1- (signal)	61
	-2- (earth)	62
Exhaust gas temperature sender 1, bank 2 -G236- Bank 2 (left-side)	-1- (signal)	20
	-2- (earth)	62

–  Repair wiring connection if necessary. If wiring is OK: –  Renew exhaust gas temperature sender: left-side → Chapter, right-side → Chapter.