Checking actuation of seat heating (optional extra) — AUDI

Checking actuation of seat heating (optional extra)
Special tools and workshop equipment required
Test box
V.A.G 1598/42
and
A/C operating element test adapter - Touran
V.A.G 1598/47
Vehicle diagnostic, testing and information system
VAS 5051 A
with
multimeter leads
VAS 5051/7
A voltage is output by way of the
heated driver seat regulator
E94
and the
heated front passenger seat regulator
E95
(a potentiometer is actuated by the corresponding knurled wheel
C
) by the
heater control unit
J65
.
The voltage supplied by the
heater control unit
J65
A
with the seat heating switched on is governed by the position of the knurled wheel and the electrical system voltage. With the engine running it is in the range between less than 0.5 V in position
“0”
and approx. 10 V in position
“5”
(measured to earth e.g. at connector
B
contact
“20”
). The voltage is transmitted via the connector
B
(from contact
“11”
to the
driver seat heating control unit
J726
and from contact
“15”
to the
front passenger seat heating control unit
J727
)
Current flow diagrams, Electrical fault finding and Fitting locations
.
Note
The resistance of the seat heating potentiometers depends on the position of the knurled wheel and cannot be measured with workshop equipment.
Checking operation of seat heating and servicing
General body repairs, interior
Rep. gr.
74
and
Current flow diagrams, Electrical fault finding and Fitting locations
As of Model Year 2009, seat heating control units are gradually being introduced on which the specified temperature for the seat heating is regulated on a lower characteristic curve
Electronic parts catalogue
.
As of Model Year 2010 a start/stop system will be available as an optional extra for this vehicle in conjunction with certain engines. On vehicles with start/stop system, the seat heating might be switched off by the
onboard supply control unit
J519
when the stop function is active (to protect the
battery
A
). Once the engine has been re-started via the start function, the seat heating is actuated again
"Guided fault-finding" function of vehicle diagnostic, testing and information system VAS 5051
.