Volvo VHD - Manual (Page 185)

Heating and Air Conditioning 179
A/C Diagnostic Module
Problem Codes
The diagnostic module has two LED lights
(one green and one red) which indicate if a
system problem has been detected. If a
problem is detected, a fault code or “blink”
code is activated to identify the condition.
The blink codes listed on the label are:
Slow Green Normal
Fast Green Low system voltage
1 Red Blink Loss of refrigerant
2 Red Blinks Overcharge, blockage or
fan failure
3 Red Blinks Open or shorted clutch
or circuit
4 Red Blinks Open pressure switch or
circuit
The air conditioning system is under
pressure. The possibility of an explosion
is possible if serviced incorrectly. A
qualified technician should perform any
service needed. Failure to follow this
may lead to an explosion causing severe
injury or death.
W3002004