Question 1

Internal Temperature Screen shows red text informing the user

Accepted Answer

Possible cause: Errors with the internal temperature sensor. Check the internal temperature screen for sensor errors and contact your dealer if the problem persists.

Question 2

Error LED is flashing 230V mode: On RM 8400/RMS 8400 refrigerator: 230V mode failure

Accepted Answer

Possible cause: Either no 230V supply is reaching the unit, or the voltage is too low.. Check mains connection and voltage.

Question 3

Error LED is flashing 12V mode: On RM 8400/RMS 8400 refrigerator: 12V mode failure

Accepted Answer

Possible cause: Either no 12V supply is reaching the unit, or the voltage is too low.. Check 12V supply and battery/charging status.

Question 4

Error LED is flashing GAS/Auto mode: On RM 8400/RMS 8400 refrigerator: Gas/Auto mode failure

Accepted Answer

Possible cause: Flame not ignited. Check gas supply and re-ignite.

Question 5

Error All temperature-setting LEDs flash: On RM 8400/RMS 8400 refrigerator: Temperature sensor failure

Accepted Answer

Possible cause: Temperature sensor defective, refrigerator works on mid temperature setting. Contact customer services.

Question 6

Error The 230V LED plus all temperature-setting LEDs flash: On RM 8400/RMS 8400 refrigerator: 230V heating element failure

Accepted Answer

Possible cause: Heating element defective. Inform Dometic Customer Services.

Question 7

Error The 12V LED plus all temperature-setting LEDs flash: On RM 8400/RMS 8400 refrigerator: 12V heating element failure

Accepted Answer

Possible cause: Heating element defective. Inform Dometic Customer Services.

Question 8

The refrigerator (RM 8400/RMS 8400) does not cool sufficiently

Accepted Answer

Possible cause: Could be poor ventilation around the unit, the thermostat set too low, a heavily frosted condenser, too much warm food stored in a short space of time, the fridge only recently switched on, or high ambient temperatures.. Make sure the ventilation grilles aren't covered, turn the thermostat up, and check the door closes properly. Let warm food cool before storing it, give the cooling compartment 4-5 hours to catch up if it's only just switched on, and clean the ventilation grilles regularly.

Question 9

RM 8400/RMS 8400 refrigerator won't cool on gas

Accepted Answer

Possible cause: Could be an empty gas cylinder, the upstream shut-off device left closed, or air trapped in the gas pipe.. Swap the gas cylinder, open the shut-off device, then switch the fridge off and on again - repeat this 3-4 times if needed.

Question 10

RM 8400/RMS 8400 refrigerator won't cool on 12V

Accepted Answer

Possible cause: On-board fuse defective; On-board battery discharged; Engine not running; Heating element defective. Fit new fuse. Check battery, charge it. Start engine. Inform Dometic Customer Services.

Question 11

RM 8400/RMS 8400 refrigerator won't cool on 230V

Accepted Answer

Possible cause: Could be a blown on-board fuse, the vehicle not connected to a mains supply, or a faulty heating element.. Fit a new fuse, connect to a mains power supply, or let Dometic Customer Services know if the heating element's at fault.

Question 12

The RML10.4S/RMD10.5X/RMS10.5XS refrigerator won't run at all when it's on AC power

Accepted Answer

Possible cause: A blown fuse in the AC supply, the vehicle simply not being plugged into AC power, or a faulty AC heating element can all cause this.. Fit a new fuse, make sure the vehicle's actually connected to an AC supply, and if it still won't run, get in touch with an authorised customer service point.

Question 13

The same refrigerator (RML10.4S/RMD10.5X/RMS10.5XS) fails to run on DC power instead

Accepted Answer

Possible cause: This can come down to a faulty fuse in the DC cable, a blown vehicle fuse, a flat vehicle battery, the ignition being off, or a faulty DC heating element.. Replace the relay's own fuse, or your vehicle's fuse (check your vehicle's handbook for which one), and make sure the ignition is switched on. Test the vehicle battery and give it a charge if needed. If the fridge still won't run after all that, get in touch with an authorised service point for further help.

Question 14

In gas mode: The refrigerator (RML10.4S/RMD10.5X/RMS10.5XS) does not work

Accepted Answer

Possible cause: Could be an empty gas cylinder, the gas valve left closed, or air trapped in the gas line.. Replace the gas cylinder, open the valve, then switch the fridge off and back on - repeat this three or four times if needed. If you have a stove fitted, try switching that on and repeating the process on the fridge.

Question 15

On automatic mode, the fridge runs on gas even though the vehicle is plugged into AC power

Accepted Answer

Possible cause: The mains voltage from the site supply is running too low. This isn't a fault as such - the fridge will switch itself back over to AC power the moment the site voltage recovers.

Question 16

The refrigerator (RML10.4S/RMD10.5X/RMS10.5XS) is not cooling adequately

Accepted Answer

Possible cause: Could be poor ventilation around the cooling unit, an iced-up evaporator, the temperature set too high, high ambient temperature, too much food loaded in at once (especially if warm), or the fridge only recently switched on.. Check the ventilation grille isn't blocked, the door closes properly, and the door seal is intact and fitted correctly. Defrost the fridge if needed and try a lower temperature setting. You can also take the grille off for a while to let warm air escape faster, thin out an overloaded fridge, or let warm food cool before loading it in - then check the temperature again after 4-5 hours.

Question 17

RML10.4S/RMD10.5X/RMS10.5XS refrigerator's temperature sensor has failed

Accepted Answer

Get in touch with an authorised customer service point.

Question 18

RML10.4S/RMD10.5X/RMS10.5XS refrigerator shows no AC power connected, or AC voltage below 190V

Accepted Answer

Connect the fridge to an AC power source, or switch to a different energy type such as gas or DC.

Question 19

DC power not connected on refrigerator (RML10.4S/RMD10.5X/RMS10.5XS)

Accepted Answer

Connect the fridge to a DC power source, or switch to a different energy type such as gas or AC.

Question 20

DC overvoltage (>16V) on refrigerator (RML10.4S/RMD10.5X/RMS10.5XS)

Accepted Answer

Reduce the DC supply voltage.

Question 21

The RML10.4S/RMD10.5X/RMS10.5XS refrigerator's tank stop mode blocks gas operation for a 15-minute period

Accepted Answer

Either let the 15 minutes pass, or switch the fridge onto a different operating mode in the meantime.

Question 22

The fridge (RML10.4S/RMD10.5X/RMS10.5XS) has had its door left open for over two minutes

Accepted Answer

Close the door.

Question 23

RML10.4S/RMD10.5X/RMS10.5XS refrigerator's power module isn't communicating with its display

Accepted Answer

Get in touch with an authorised customer service point.

Question 24

No cooling capacity in gas mode on refrigerator (RML10.4S/RMD10.5X/RMS10.5XS)

Accepted Answer

Check whether the fridge is sitting at an angle and level it if needed, then reset the error - if it comes back, contact customer service.

Question 25

No cooling capacity in AC power mode on refrigerator (RML10.4S/RMD10.5X/RMS10.5XS)

Accepted Answer

Check whether the fridge is sitting at an angle and level it if needed, then reset the error - if it comes back, contact customer service.

Question 26

Refrigerator (RML10.4S/RMD10.5X/RMS10.5XS) isn't cooling at all while running on DC power

Accepted Answer

Check the fridge is sitting level and adjust it if it's tilted, then reset the fault. If it comes back again, contact customer service.

Question 27

Gas valve test error on refrigerator (RML10.4S/RMD10.5X/RMS10.5XS)

Accepted Answer

Gas operation won't be possible until this clears - reset the error, and contact customer service if it keeps recurring.

Question 28

Internal communication error on refrigerator (RML10.4S/RMD10.5X/RMS10.5XS)

Accepted Answer

Gas operation won't be possible until this clears - reset the error, and contact customer service if it keeps recurring.

Question 29

In stand-alone gas mode, the RML10.4S/RMD10.5X/RMS10.5XS refrigerator's battery packs are too low on charge

Accepted Answer

Fit fresh batteries, then reset the error.

Question 30

Gas lock after 3 ignition attempts on refrigerator (RML10.4S/RMD10.5X/RMS10.5XS)

Accepted Answer

Possible cause: Ignition is not possible; The gas cylinder is empty. Replace the gas cylinder, then reset the error.

Question 31

Error Gas lock (internal power-module error): Gas lock triggered by an internal power-module error

Accepted Answer

Reset the error, and get in touch with customer service if it happens again.

Error Code / Indicator	Symptom / Meaning	Possible Cause	Step-by-Step DIY Fix	Suggested Actions
`N/A`	Internal Temperature Screen shows red text informing the user	Errors with the internal temperature sensor	Check the internal temperature screen for sensor errors and contact your dealer if the problem persists.	DIY Check / Tech Fallback
`LED is flashing 230V mode`	On RM 8400/RMS 8400 refrigerator: 230V mode failure	Either no 230V supply is reaching the unit, or the voltage is too low.	Check mains connection and voltage.	DIY Safe
`LED is flashing 12V mode`	On RM 8400/RMS 8400 refrigerator: 12V mode failure	Either no 12V supply is reaching the unit, or the voltage is too low.	Check 12V supply and battery/charging status.	DIY Safe
`LED is flashing GAS/Auto mode`	On RM 8400/RMS 8400 refrigerator: Gas/Auto mode failure	Flame not ignited	Check gas supply and re-ignite.	DIY Safe
`All temperature-setting LEDs flash`	On RM 8400/RMS 8400 refrigerator: Temperature sensor failure	Temperature sensor defective, refrigerator works on mid temperature setting	Contact customer services.	Professional Intervention Required
`The 230V LED plus all temperature-setting LEDs flash`	On RM 8400/RMS 8400 refrigerator: 230V heating element failure	Heating element defective	Inform Dometic Customer Services.	Professional Intervention Required
`The 12V LED plus all temperature-setting LEDs flash`	On RM 8400/RMS 8400 refrigerator: 12V heating element failure	Heating element defective	Inform Dometic Customer Services.	Professional Intervention Required
`N/A`	The refrigerator (RM 8400/RMS 8400) does not cool sufficiently	Could be poor ventilation around the unit, the thermostat set too low, a heavily frosted condenser, too much warm food stored in a short space of time, the fridge only recently switched on, or high ambient temperatures.	Make sure the ventilation grilles aren't covered, turn the thermostat up, and check the door closes properly. Let warm food cool before storing it, give the cooling compartment 4-5 hours to catch up if it's only just switched on, and clean the ventilation grilles regularly.	DIY Safe
`N/A`	RM 8400/RMS 8400 refrigerator won't cool on gas	Could be an empty gas cylinder, the upstream shut-off device left closed, or air trapped in the gas pipe.	Swap the gas cylinder, open the shut-off device, then switch the fridge off and on again - repeat this 3-4 times if needed.	DIY Safe
`N/A`	RM 8400/RMS 8400 refrigerator won't cool on 12V	On-board fuse defective; On-board battery discharged; Engine not running; Heating element defective	Fit new fuse. Check battery, charge it. Start engine. Inform Dometic Customer Services.	DIY Check / Tech Fallback
`N/A`	RM 8400/RMS 8400 refrigerator won't cool on 230V	Could be a blown on-board fuse, the vehicle not connected to a mains supply, or a faulty heating element.	Fit a new fuse, connect to a mains power supply, or let Dometic Customer Services know if the heating element's at fault.	DIY Check / Tech Fallback
`N/A`	The RML10.4S/RMD10.5X/RMS10.5XS refrigerator won't run at all when it's on AC power	A blown fuse in the AC supply, the vehicle simply not being plugged into AC power, or a faulty AC heating element can all cause this.	Fit a new fuse, make sure the vehicle's actually connected to an AC supply, and if it still won't run, get in touch with an authorised customer service point.	DIY Check / Tech Fallback
`N/A`	The same refrigerator (RML10.4S/RMD10.5X/RMS10.5XS) fails to run on DC power instead	This can come down to a faulty fuse in the DC cable, a blown vehicle fuse, a flat vehicle battery, the ignition being off, or a faulty DC heating element.	Replace the relay's own fuse, or your vehicle's fuse (check your vehicle's handbook for which one), and make sure the ignition is switched on. Test the vehicle battery and give it a charge if needed. If the fridge still won't run after all that, get in touch with an authorised service point for further help.	DIY Check / Tech Fallback
`N/A`	In gas mode: The refrigerator (RML10.4S/RMD10.5X/RMS10.5XS) does not work	Could be an empty gas cylinder, the gas valve left closed, or air trapped in the gas line.	Replace the gas cylinder, open the valve, then switch the fridge off and back on - repeat this three or four times if needed. If you have a stove fitted, try switching that on and repeating the process on the fridge.	DIY Safe
`N/A`	On automatic mode, the fridge runs on gas even though the vehicle is plugged into AC power	The mains voltage from the site supply is running too low	This isn't a fault as such - the fridge will switch itself back over to AC power the moment the site voltage recovers.	DIY Safe
`N/A`	The refrigerator (RML10.4S/RMD10.5X/RMS10.5XS) is not cooling adequately	Could be poor ventilation around the cooling unit, an iced-up evaporator, the temperature set too high, high ambient temperature, too much food loaded in at once (especially if warm), or the fridge only recently switched on.	Check the ventilation grille isn't blocked, the door closes properly, and the door seal is intact and fitted correctly. Defrost the fridge if needed and try a lower temperature setting. You can also take the grille off for a while to let warm air escape faster, thin out an overloaded fridge, or let warm food cool before loading it in - then check the temperature again after 4-5 hours.	DIY Safe
`N/A`	RML10.4S/RMD10.5X/RMS10.5XS refrigerator's temperature sensor has failed	—	Get in touch with an authorised customer service point.	Professional Intervention Required
`N/A`	RML10.4S/RMD10.5X/RMS10.5XS refrigerator shows no AC power connected, or AC voltage below 190V	—	Connect the fridge to an AC power source, or switch to a different energy type such as gas or DC.	DIY Safe
`N/A`	DC power not connected on refrigerator (RML10.4S/RMD10.5X/RMS10.5XS)	—	Connect the fridge to a DC power source, or switch to a different energy type such as gas or AC.	DIY Safe
`N/A`	DC overvoltage (>16V) on refrigerator (RML10.4S/RMD10.5X/RMS10.5XS)	—	Reduce the DC supply voltage.	DIY Safe
`N/A`	The RML10.4S/RMD10.5X/RMS10.5XS refrigerator's tank stop mode blocks gas operation for a 15-minute period	—	Either let the 15 minutes pass, or switch the fridge onto a different operating mode in the meantime.	DIY Safe
`N/A`	The fridge (RML10.4S/RMD10.5X/RMS10.5XS) has had its door left open for over two minutes	—	Close the door.	DIY Safe
`N/A`	RML10.4S/RMD10.5X/RMS10.5XS refrigerator's power module isn't communicating with its display	—	Get in touch with an authorised customer service point.	Professional Intervention Required
`N/A`	No cooling capacity in gas mode on refrigerator (RML10.4S/RMD10.5X/RMS10.5XS)	—	Check whether the fridge is sitting at an angle and level it if needed, then reset the error - if it comes back, contact customer service.	DIY Check / Tech Fallback
`N/A`	No cooling capacity in AC power mode on refrigerator (RML10.4S/RMD10.5X/RMS10.5XS)	—	Check whether the fridge is sitting at an angle and level it if needed, then reset the error - if it comes back, contact customer service.	DIY Check / Tech Fallback
`N/A`	Refrigerator (RML10.4S/RMD10.5X/RMS10.5XS) isn't cooling at all while running on DC power	—	Check the fridge is sitting level and adjust it if it's tilted, then reset the fault. If it comes back again, contact customer service.	DIY Check / Tech Fallback
`N/A`	Gas valve test error on refrigerator (RML10.4S/RMD10.5X/RMS10.5XS)	—	Gas operation won't be possible until this clears - reset the error, and contact customer service if it keeps recurring.	DIY Check / Tech Fallback
`N/A`	Internal communication error on refrigerator (RML10.4S/RMD10.5X/RMS10.5XS)	—	Gas operation won't be possible until this clears - reset the error, and contact customer service if it keeps recurring.	DIY Check / Tech Fallback
`N/A`	In stand-alone gas mode, the RML10.4S/RMD10.5X/RMS10.5XS refrigerator's battery packs are too low on charge	—	Fit fresh batteries, then reset the error.	DIY Safe
`N/A`	Gas lock after 3 ignition attempts on refrigerator (RML10.4S/RMD10.5X/RMS10.5XS)	Ignition is not possible; The gas cylinder is empty	Replace the gas cylinder, then reset the error.	DIY Safe
`Gas lock (internal power-module error)`	Gas lock triggered by an internal power-module error	—	Reset the error, and get in touch with customer service if it happens again.	DIY Check / Tech Fallback

Elddis Refrigeration & Cooling

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Master Troubleshooting & Diagnostics Matrix