Basic Troubleshooting - Webasto Thermo Top C Operating And Installation Instructions

Thermo Top C (TTC)
6.

Basic Troubleshooting

6.1 General Information
This section describes troubleshooting procedures for the TTC coolant heater.
Troubleshooting is normally limited to the isolation of defective components.
Troubleshooting requires profound knowledge about structure and theory of operation of the heater
components and may only be performed by skilled personnel.
Before troubleshooting, check for and eliminate these defects:
- blown fuses
- fuel supply (plugged fuel filter)
- corrosion on battery terminals, electrical wiring, connections and fuses
- loose contact on connectors
- wrong crimping on connectors
After any correction of a defect a functional test has to be performed in the vehicle.
6.2 General Failure Symptoms
The following table lists possible failure symptoms.
Failure Symptom
Coolant heater
switches off
automatically
(Fault lockout)
Heater expels black
fumes from exhaust
Table 601: General Failure Symptoms
Probable Cause
No combustion after start
or automatic repeat start
Flame extinguishes during
operation
Heater overheats
Vehicle electrical system
voltage too low
Combustion air and/or
exhaust ducting blocked
CAUTION
NOTE
Remedy
Switch off heater momentarily and switch on once again
Switch off heater momentarily and switch on once again
Check coolant lines for obstructions, closed valves and kinks.
Check coolant level. Allow heater to cool down, reset over heat
limiter, switch off heater momentarily and switch on once again
Charge battery
Switch off heater momentarily and switch on once again
Check combustion and exhaust ducting for obstructions
6 Basic Troubleshooting
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