Question 1

No LED is on, the appliance is switched on and is supplied with operating voltage

Accepted Answer

Possible cause: Automatic restart is blocked, e.g. after a power failure. Reset by switching off, waiting 5 seconds and then switching on again.

Question 2

No LED illuminates after switching on

Accepted Answer

Possible cause: No operating voltage or appliance/vehicle fuse defective. Check 12 V battery voltage, charge battery if necessary, check all electrical plug connections, and check the fuse of the appliance or vehicle and replace if necessary.

Question 3

The green LED illuminates when the appliance is switched on, but the heater does not operate

Accepted Answer

Possible cause: The temperature setting on the control panel is lower than the room temperature. Select a higher room temperature at the control panel.

Question 4

Heater continues operating with risk of low voltage

Accepted Answer

Possible cause: Battery voltage too low < 10.4 V (Gas heater) or < 11.5 V (Diesel heater). Charge battery. For diesel heater, use electrical power from battery sparingly.

Question 5

Heater not functioning due to low voltage or overvoltage

Accepted Answer

Possible cause: Battery voltage too low < 10.0 V / < 10.2 V or overvoltage > 16.4 V. Charge battery or replace old battery. For overvoltage, check battery voltage and voltage sources such as the charger.

Question 6

Heater stops operating

Accepted Answer

Possible cause: Open window above cowl detected by window switch. Close the window.

Question 7

Heater switches to failure after operating for a longer period of time

Accepted Answer

Possible cause: Summer mode with empty water container, warm air outlets blocked, or circulated air intake blocked. Switch appliance off, allow to cool, fill boiler with water, check individual outlet openings, and remove circulated air intake blockage.

Question 8

Heater indicates sensor fault

Accepted Answer

Possible cause: Room temperature sensor or cable faulty. Contact an authorised service agent.

Question 9

Heater indicates control panel fault

Accepted Answer

Possible cause: Control panel or control panel cable defective. Contact an authorised service agent.

Question 10

Heater indicates short circuit in FrostControl

Accepted Answer

Possible cause: FrostControl heating element has a short circuit. Disconnect heating element plug from electronic control unit and have the heating element replaced by a specialist.

Question 11

Heater fails approx. 30 seconds after switching on

Accepted Answer

Possible cause: Gas cylinder or quick-acting valve closed, gas cylinder empty, gas pressure regulation system iced up, or butane content in gas cylinder too high. Check gas supply and open valves, replace gas cylinder, use regulator heater (EisEx), or use propane.

Question 12

Heater fault

Accepted Answer

Possible cause: Heater electronics fault. Determine the flashing code and contact an authorised service agent.

Question 13

Green LED still illuminated after the heater has been switched off

Accepted Answer

Possible cause: After-running is active to reduce the temperature of the appliance. No fault. After-run switches itself off after a maximum of 5 minutes.

Question 14

Room heating does not react to adjustment immediately

Accepted Answer

Possible cause: After-running is active to reduce the temperature of the appliance. No fault. After-run switches itself off after a maximum of 5 minutes.

Question 15

After switching on, the green and red LED illuminate

Accepted Answer

Possible cause: Faulty electronics. Contact an authorised service agent.

Question 16

Diesel heater fails to start

Accepted Answer

Possible cause: Lack of fuel due to insufficient fuel tank filling, tank ran empty, and/or vehicle is on a slope. Fill tank with fuel, then fill fuel line as described in initial start-up instructions.

Error Code / Indicator	Symptom / Meaning	Step-by-Step DIY Fix	Suggested Actions
`N/A`	No LED is on, the appliance is switched on and is supplied with operating voltage Possible Cause: Automatic restart is blocked, e.g. after a power failure	Reset by switching off, waiting 5 seconds and then switching on again.	DIY Safe
`N/A`	No LED illuminates after switching on Possible Cause: No operating voltage or appliance/vehicle fuse defective	Check 12 V battery voltage, charge battery if necessary, check all electrical plug connections, and check the fuse of the appliance or vehicle and replace if necessary.	DIY Safe
`N/A`	The green LED illuminates when the appliance is switched on, but the heater does not operate Possible Cause: The temperature setting on the control panel is lower than the room temperature	Select a higher room temperature at the control panel.	DIY Safe
`Operational Fault`	Heater continues operating with risk of low voltage Possible Cause: Battery voltage too low < 10.4 V (Gas heater) or < 11.5 V (Diesel heater)	Charge battery. For diesel heater, use electrical power from battery sparingly.	DIY Safe
`Operational Fault`	Heater not functioning due to low voltage or overvoltage Possible Cause: Battery voltage too low < 10.0 V / < 10.2 V or overvoltage > 16.4 V	Charge battery or replace old battery. For overvoltage, check battery voltage and voltage sources such as the charger.	DIY Safe
`Operational Fault`	Heater stops operating Possible Cause: Open window above cowl detected by window switch	Close the window.	DIY Safe
`Operational Fault`	Heater switches to failure after operating for a longer period of time Possible Cause: Summer mode with empty water container, warm air outlets blocked, or circulated air intake blocked	Switch appliance off, allow to cool, fill boiler with water, check individual outlet openings, and remove circulated air intake blockage.	DIY Safe
`Operational Fault`	Heater indicates sensor fault Possible Cause: Room temperature sensor or cable faulty	Contact an authorised service agent.	Professional Intervention Required
`Operational Fault`	Heater indicates control panel fault Possible Cause: Control panel or control panel cable defective	Contact an authorised service agent.	Professional Intervention Required
`Operational Fault`	Heater indicates short circuit in FrostControl Possible Cause: FrostControl heating element has a short circuit	Disconnect heating element plug from electronic control unit and have the heating element replaced by a specialist.	DIY Check / Tech Fallback
`Operational Fault`	Heater fails approx. 30 seconds after switching on Possible Cause: Gas cylinder or quick-acting valve closed, gas cylinder empty, gas pressure regulation system iced up, or butane content in gas cylinder too high	Check gas supply and open valves, replace gas cylinder, use regulator heater (EisEx), or use propane.	DIY Safe
`Operational Fault`	Heater fault Possible Cause: Heater electronics fault	Determine the flashing code and contact an authorised service agent.	Professional Intervention Required
`N/A`	Green LED still illuminated after the heater has been switched off Possible Cause: After-running is active to reduce the temperature of the appliance	No fault. After-run switches itself off after a maximum of 5 minutes.	DIY Safe
`N/A`	Room heating does not react to adjustment immediately Possible Cause: After-running is active to reduce the temperature of the appliance	No fault. After-run switches itself off after a maximum of 5 minutes.	DIY Safe
`N/A`	After switching on, the green and red LED illuminate Possible Cause: Faulty electronics	Contact an authorised service agent.	Professional Intervention Required
`Operational Fault`	Diesel heater fails to start Possible Cause: Lack of fuel due to insufficient fuel tank filling, tank ran empty, and/or vehicle is on a slope	Fill tank with fuel, then fill fuel line as described in initial start-up instructions.	DIY Safe

Truma CP E Classic

Technical Specifications

Master Troubleshooting & Diagnostics Matrix