BMW 1992 525i Electrical Troubleshooting Manual page 418

IBstiiNTEGRATED CLIMATE REGULATION WITH FILTER (IHKR/F3)
..... .....
co
N
Pin
Type Description/Function Connection
Type of Signal Tester Display Measurement Notes
15 A Diagnosis RxD
Diagnostic connector
Frequency
16 E Diagnosis TxD
Diagnostic connector
Frequency
17 Not used
18 A
Switching unit sensor fan activation Control switch
approx. OV At lgnHion ON
approx. 12V approx. 3 minutes after
Ignition OFF
19 A
Auxiliary water pump activation Relay, auxiliary water pump
Ground
20
A Rear window defogger activation Rear window defogger relay approx. 0 V
ON
approx. 12 V OFF
21
Not used
22 A Activation,
NC
compressor DME control unit approx. OV ON m
approx. 12 V OFF
~
U1
23 A Mixing flap motor activation Mixing flap motor Frequency 0% - 82% at ventilation
approx. 11 V with motor
0
.
Ul
(square-wave
flap switch OFF OFF
I
....
voltage) 1 00% at ventilation
switch ON
24
A Mixing flap motor activation Mixing flap motor Frequency 0%-82% at ventilation
approx. 11 V with motor
(square-wave flap switch OFF
OFF
voltage) 100% at ventilation
switch ON
25 A Mixing flap motor activation Mixing flap motor Frequency 0% - 82% at ventilation
approx. 11 V with motor
(square-wave flap switch OFF OFF
voltage) 1 00% at ventilation
switch ON
26
A
Mixing 11ap ·motor activation Mixing flap motor Frequency 0%- 82% at ventilation
approx. 11 V with motor
(square-wave) flap switch OFF
OFF
100% at ventilation
switch ON
...
CD
CD
N
(