LR3/Disco 3
Cavity
Description
Typical Condition -
No fault
DTC
PID
Symptom
Input/Output Possible Cause
1
Cavity not used n/a
n/a
n/a
n/a
n/a
n/a
2
Cavity not used n/a
n/a
n/a
n/a
n/a
n/a
3
Recirculation
motor
power/ground
0V, switches to
battery voltage
while motor drives
flap to recirculated
air
B1B6801
9976
Air intake flap
cannot be
adjusted
Input/Output
Recirculation
motor fault,
wiring short
circuit or open
circuit. Also see
Note below
4
Recirculation
motor
power/ground
0V, switches to
battery voltage
while motor drives
flap to fresh air
B1B6801
9976
Air intake flap
cannot be
adjusted
Input/Output
Recirculation
motor fault,
wiring short
circuit or open
circuit. Also see
Note below
5
Cavity not used n/a
n/a
n/a
n/a
n/a
n/a
6
Cavity not used n/a
n/a
n/a
n/a
n/a
n/a
7
Cavity not used n/a
n/a
n/a
n/a
n/a
n/a
8
Cavity not used n/a
n/a
n/a
n/a
n/a
n/a
9
Recirculation
motor signal
Approximately 1V
when flap in fresh
air position, 4V
when flap in
recirculation
position
B1B6711
9958
Air intake flap
cannot be
adjusted
Input
Short circuit to
ground. Also see
Note below
9
Recirculation
motor signal
Approximately 1V
when flap in fresh
air position, 4V
when flap in
recirculation
position
B1B6715
9958
Air intake flap
cannot be
adjusted
Input
Open circuit,
short circuit high
10
Cavity not used n/a
n/a
n/a
n/a
n/a
n/a
11
Motor ground
Voltage should be
similar to that seen
on C2655-3
None
None
Most motors
inoperative. Very
poor A/C
performance
Output
Open circuit
12
Sensor ground
Voltage should be
similar to that seen
on C2655-3
B1B6313
None
No cooling. Air
intake flap
cannot be
adjusted
Output
Open circuit,
short circuit to
12V
13
Distribution and
temperature
blend motor
power
Battery voltage
when CAN bus is
awake
B1B7400,
B1B7500,
B1B7600,
B1B7700
99A2
Most actuators
don't work. Poor
A/C operation
Input
Short circuit to
ground, open
circuit
13
Distribution and
temperature
blend motor
Battery voltage
when CAN bus is
None
99A2
Current
consumption
abnormally high
Input
Short circuit to
12V
