Troubleshooting; General Information; General Error Symptoms - Webasto Air Top Evo 40 Series Service Manual

5.0

Troubleshooting

5.1

General Information

If a malfunction occurs, a flashing code is displayed on the operating indicator or a fault code F .. on the combination
timer.
In addition, the heater can be checked using a personal computer (see Webasto PC Thermo Test PC Diagnosis operating
manual).
IMPORTANT: Troubleshooting work demands precise knowledge of the structure and theory of operation of the various
components and must be carried out by trained personnel only. The functional relationships are described in Chapter 2
and 3.
IMPORTANT: The troubleshooting guide is restricted to the localization of defective components.
The following fault causes should always be checked or a fault should be excluded for the following reasons:
– Corrosion on connector
– Loose connection on connector
– Poor crimp contacts on plugs
– Corrosion on lines and fuses
– Corrosion on battery terminals
If you wish to check individual components, the electrical plug connectors on the control unit must be disconnected.
Conduct a function test in the vehicle after rectifying each fault.
A direct operation of the individual components (with voltage) is not permitted.
5.2

General Error Symptoms

The following table lists possible fault symptoms.
Error S ymptom
Heater cuts out automatically
Heater emits black smoke
General Error Symptoms
Air Top Evo 40 / Air Top Evo 55 Service Manual
Possible Cause
No combustion after starting and restarting
Operating display flashes
Flame extinguishes during operation
Operating display flashes
Heater overheated
Operating display flashes
Vehicle voltage too low
Operating display flashes
Combustion air and/or exhaust system
blocked
21
Remedy
Switch heater off and then on again
Switch heater off and then on again
Check the hot air guide for free passage, al-
low the heater to cool down, then briefly
switch the heater off and then on again
Charge battery
Switch heater off and then on again
Check that the combustion air and exhaust
systems are clear