Webasto DUAL TOP RHA-100 Workshop Manual - page 10
3 Fault code output
Dual Top
302
Table 301: Fault messages manual Control Panel
Number of
RED flashes
Meaning
Remedy
00
No communication between Control Panel and
heater, or error Control Panel
1 First, remove fuses 15A and 5A. Then put in fuse 15A,
followed by fuse 5A.
2 Check connections of Control Panel.
3 Check fuse 15A.
4 Check wiring harness.
5 Replace Control Panel (see chapter 6: "Servicing
work").
6 Replace control unit.
01
No start (after 2 attempts to start)
1 Check fuel supply (enough fuel, at least 8 ltr.; check
fuel connection and tubes), reset heater (by switching
off for at least 30 sec.).
2 Clean burner insert.
02
Flame failure (at least > 3)
1 Check fuel supply (enough fuel, at least 8 ltr.; check
fuel connection and tubes), reset heater (by switching
off for at least 30 sec.).
2 Clean burner insert.
03
Under voltage or over voltage
Charge battery or connect to another power source (DC,
12V or charger 230V),
reset heater (by switching off for at least 5 sec.)
04
Fuel pump disconnection / short circuit /
overheating
1 Check fuel pump cable and connectors.
2 Check internal wiring harness connections Y9, Y10.
05
Hot air motor fault: disconnection / short circuit
/ fan speed out of range / fan blocked
1 Let heater cool down.
Check power supply:
Fuse correct (fuse not damaged, 10A fuse used for
PWM module) and functioning.
All contacts are correct (no corrosion).
Voltage correct (>12V).
Restart heater.
2 Start blower: component test in diagnostic mode.
Run blower 5 minutes at 80%.
Listen if there is any unusual noise (grinding, etc.).
Restart heater.
3 Dismount application parts until the fan is visible.
Check if dirt, screws, objects or deformations block
the fan.
Check fan clearance with your finger (no high force!).
Remove all matters that block the fan.
Restart heater.
4 Remove service cap.
Check all electrical connectors.
Moisture in connectors (2-pin connector and 4-pin
connector)?
Moisture in connectors or on PWM module?
PWM module dark or burned?
12V power supply permanently available at PWM
module? (measure voltage between brown and red/
blue cable contacts of 4-pin connector) If not, check
external wiring harness: routing wiring harness and
pins of 12 pin connector.
In case there is a bad connector, bad wiring harness or
defect PWM module: replace defect part.
5 If heating air blower assy and wiring harness have
been checked and Dual Top still doesn’t run: replace
complete Dual Top.
06
Overheating or exceeding gradient water
temperature sensor
1 Check water level, reset heater (by switching off for at
least 5 sec.) or select winter mode without hot water
production.
2 Check fuel pump cable and connectors.
3 Check if hot and cold water pipes have been
connected correctly.
4 Check internal wiring harness connections Y9, Y10.