Fault Codes for Espar D2 & D4 Heaters

What are the fault codes for Eberspächer / Espar D2 & D4 heaters?

Fault code

Description

Comments/remedy

000

No faults

 

004

Warning: Short circuit in control box, fresh air output

• Disconnect connector S1 / B1 at the heater and at the connector B1, PIN 16 check the cable up to the fresh air fan relay for short circuit to negative.

– If OK —> replace control box.

005

Warning: Short circuit in control box, car alarm output

• Disconnect connector S1 / B1 at the heater and at the connector B1, PIN 15 check the cable up to the relay isolating switch or burglar alarm system input for short circuit to negative. 

– If OK —> replace control box.

006

Warning: Inexplicable atmospheric altitude information (Display only if heaters labelled “H-Kit” on the nameplate.)


Control box has not received any explicable altitude information. 

• Read out fault memory in the air pressure sensor using the EDiTH diagnostics tool and correct fault.

009 

Cut-off ADR

ADR shutdown due to signal change from (+) to (–) at connector S1, PIN 13 (D+) or plus signal at connector S1, PIN 14 (HA+).

010

Overvoltage – cut-off


Overvoltage applied to control box for at least 20 seconds without interruption – heater not working. 

• Disconnect connector S1 / B1 at the heater, start the vehicle’s engine, measure the voltage at connector B1 between PIN 1 (cable 2.52 rt) and PIN 10 (cable 2.52 br).  


– Airtronic 12 volt – voltage >16 volt —> check generator regulator.

 

– Airtronic 24 volt – voltage >32 volt —> check generator regulator.

011

Undervoltage – cut-off


Undervoltage applied to control box for at least 20 seconds without interruption – heater not working. 

• Disconnect connector S1 / B1 at the heater, the vehicle’s engine is switched off, measure the voltage at connector B1 between PIN 1 (cable 2.52 rt) and PIN 10 (cable 2.52 br). 

 

The measured value and the voltage at the battery should be the same.


• In case of a voltage drop, check the fuses, the supply cables, the negative connections and the positive support point on the battery for corrosion and correct contact.

012

Overheating at the overheating sensor (combination sensor)


Temperature of the overheating sensor too high.

• Check hot air pipes for blockage –> remove blockage.


• Sum of the component ratings of air-conducting parts is too large –> Check air system, if necessary re-lay – for component ratings, please refer to additional parts catalogue.


• Check overheating sensor.

– If OK –> measure fuel quantity.

013

Overheating at the flame sensor (combination sensor)


Flame sensor signals temperature at heat exchanger is too high.

• Check hot air pipes for blockage –> remove blockage.


• Sum of the component ratings of air-conducting parts is too large –> Check air system, if necessary re-lay – for component ratings, please refer to additional parts catalogue.


• Check flame sensor.

– If OK –> check overheating sensor. 

– If overheating sensor defective –> replace combination sensor.

– If overheating sensor OK –> measure. 

014

Temperature difference between flame sensor and overheating sensor too large

• Check hot air pipes for blockage –> remove blockage.


• Sum of the component ratings of air-conducting parts is too large –> Check air system, if necessary re-lay – for component ratings, please refer to additional parts catalogue.


• Check flame sensor.

– If OK –> check overheating sensor. 

– If overheating sensor defective –> replace combination sensor. 

– If overheating sensor OK –> measure fuel quantity

– If fuel quantity OK –> replace control box.

015

Operating lock-out


The fault code 015 is displayed, if the heater was switched back on after the fault code display 017.


The hardware threshold value for the overheating sensor has been exceeded –> the control box is locked.

• Switch off control box

017

Overheating


The hardware threshold value for the overheating sensor has been exceeded, because the control box failed to recognise the fault code 012 or 013 –> the control box is locked.


If the heater is switched on again, the fault code 015 is displayed.

• Switch off control box

020

Glow plug – interruption

• Check glow plug is working and for continuity.

– 12 volt heater – approx. 0.6 Ω ± 0.04 Ω (heat resistance)

– 24 volt heater – approx. 2 Ω ± 0.2 Ω (heat resistance)


• If the values of the continuity test and functional test are OK –> check the glow plug’s lead harness for damage and continuity.

– If OK –> replace control box.

021

Glow plug output (–), overload or earth short circuit

• Check glow plug is working and for continuity.

– 12 volt heater – approx. 0.6 Ω ± 0.04 Ω (heat resistance)

– 24 volt heater – approx. 2 Ω ± 0.2 Ω (heat resistance)


• If the values of the continuity test and functional test are OK –> check the glow plug’s lead harness for damage and continuity, 

– If OK –> replace control box.

022

Glow plug, output (+), short circuit after UB (battery voltage)

• Check glow plug lead harness for correct laying and damage. 

– If OK —> check lead harness for continuity.

– If OK —> replace control box.

025

Diagnostics cable bl/ws – short circuit – after UB (battery voltage)


This fault code cannot be displayed as the diagnostics cable is probably defective.

• Check diagnostics cable for correct laying and possible damage.

031

Blower motor interruption

• Check that the lead harness of the blower motor has been correctly laid and for damage.

– If OK –> remove lead harness at control box and check for continuity. 

– If OK –> replace control box.

032

Blower motor – short circuit after negative


Note!

Ensure compliance with test voltage. Component is destroyed if voltage value is exceeded.

Ensure power pack has adequate short-circuit resistance – min 20 A.

• Carry out functional test on the blower motor. To do this, remove the connector from the control box.

Apply a voltage of 11.3 v or 23.6 V ±0.1 v to the blower motor and measure the current intensity after 40 sec.


• Check wiring for short circuit.

033

Blower motor won’t rotate or short circuit after negative


Speed deviation > 10% from setpoint value for longer than 30 seconds.


Note!

Ensure compliance with test voltage. Component is destroyed if voltage value is exceeded.

Ensure power pack has adequate short-circuit resistance – min 20 A.

• Speed too low:

– Blower blocks – check blower for free running, if necessary remove foreign body.

– If OK –> check blower.


• Speed too high:

– Magnet missing from blower impeller –> replace blower.

– Speed sensor in control box is defective –> replace control box.


• Check wiring for short circuit.

034

Blower motor outlet (+), short circuit after UB (battery voltage)

• Check that the lead harness of the blower motor has been correctly laid and check for damage. – If OK —> remove lead harness at control box and check for

continuity. 

– If OK —> replace control box.

047

Metering pump short circuit or overload

• Remove connector from the metering pump. 

If the fault code 048 (interruption) is displayed the metering pump is defective –> replace metering pump.


• If the fault code 047 continues to be displayed, disconnect connector S1 / B1 at the heater, and at the connector B1, PIN 5 check the cable 12 gn / rt up to the metering pump for short circuit to negative (PIN 10), 

– If OK –> replace control box.

048

Metering pump interruption

• Remove connector from the metering pump and measure the resistance value of the metering pump (12 V = 9,5 Ω ±0.5 Ω / 24 V = 36 Ω ±1.8 Ω).

– If resistance value OK –> reconnect cable loom to the metering pump.


• Disconnect connector S1 / B1 at the heater and measure the resistance value between PIN 5 and PIN 10.

– If OK –> replace control box.

049

Metering pump outlet (+),

short circuit after UB (battery voltage)

• Check that the lead harness of the metering pump has been correctly laid and check for damage. – If OK —> remove lead harness and check for continuity.

– If OK —> replace control box.

050

Too many failed start attempts (operating lock-out)


The control box locks after too many failed start attempts (max. 255 start attempts).

• Unlock the control box by deleting the fault memory using the EDiTH customer service program, diagnostic unit or various control units.

051

Flame detected when switching on


If, after being switched on, the resistance value of the flame sensor is 1274 Ω

(> 70 °C) the heater’s fan rungs for approx. 15 min to cool down. If the resistance does not fall below the aforementioned value within 15 min the heater is switched off.

• Check the flame sensor.

052

Safety time exceeded


No flame detected during the start phase.

• Check exhaust and combustion air system.

• Check fuel supply / measure fuel quantity,

• Check spark plug (see fault code 020 and 021).

• Check flame sensor.
If OK –> replace control box.


053
054
055
056

Flame cutout in the 


„POWER“ control stage

„HIGH“ control stage

„MEDIUM“ control stage

„LOW“ control stage


The Eberspacher heater has ignited (flame detected) and signals flame cutout during a power stage.

• Check exhaust and combustion air system.


• Check fuel supply / measure fuel quantity.


• Check flame sensor

If OK –> replace control box.

060

External room temperature sensor – interruption

• Disconnect the plug-in connection of the external room temperature sensor and measure the resistance value.

– If temperature sensor OK –> reconnect plug-in connection.


• Disconnect connector S1 / B1 at the heater and measure the resistance value in connector housing B1 between PIN 6 and PIN 12. 

– If resistance value ok –> replace control box.

061

External room temperature sensor – short circuit

• Disconnect plug-in connection of the external room temperature sensor.

– If error code 060 is displayed –> check external room temperature sensor.

– If external room temperature sensor ok –> check the connection cables 0.52 gr and 0.52 br/ws for short circuit.

– If OK –> reconnect plug-in connection.


• Disconnect connector S1 / B1 at the heater and measure the resistance value in connector housing B1 between PIN 6 and PIN 12.

– If error 061 continues to be displayed –> replace control box.

062

Control unit – interruption


Heater runs in “High” control stage only

• Remove connector at the control unit and measure the resistance value of the setpoint potentiometer, for connector pins. 

– If resistance value OK –> reconnect connector at the control unit.


• Disconnect connector S1 / B1 at the heater and measure the resistance value between PIN 6 and PIN 7 in connector housing B1.

– If resistance value OK –> replace the control box. 

063

Control unit – short circuit


Fault recognition only works in heating mode. If, on the other hand, the short circuit has already occurred and then the heater is switched on, „Ventilation“ is active (not a fault code).

• If „Ventilate“ switch is installed, disconnect it and check it is working. 

– If not OK –> replace switch.


• Disconnect connector at control unit.

– If control unit OK –> check connection cables 0.5 gr/rt and 0.5 br/ws for short circuit.

– If OK –> reconnect connector at control unit. 

  

• Disconnect connector S1 / B1 at the heater.

 – If the error 063 continues to be displayed –> replace control box.

064

Flame sensor – interruption

• Dismantle control box, disconnect green connector from control box.

Check flame sensor, for diagram and table of values.

– If flame sensor OK –> replace control box.

065

Flame sensor – short circuit

• Dismantle control box, remove green connector from control box.

– If error 064 is displayed –> replace combination sensor.

– If error 065 continues to be displayed –> replace control box.

071

Overheating sensor – interruption

• Dismantle control box, disconnect blue and green connectors from control

box. 

– Measure resistance value at the blue connector PIN 1 (cable 0.52 bl) and

at the green connector PIN 2 (cable 0.52 br / ws).

– If OK –> replace control box.

072

Overheating sensor – short

circuit

• Dismantle control box, remove blue connector from control box.

– If error 071 is displayed –> replace combination sensor.

– If error 072 continues to be displayed –> replace control box.

074

Control box defective

• Overheating threshold value is not detected by control box —> replace control box.

090

Control box defective

(internal fault)

• Replace control box.

091

External interference voltage


Control box fault due to interference voltages from the vehicle’s electrical system. 

• Possible causes:


Poor battery, charger –> remove interference voltage.

092

Control box defective

(ROM error)

• Replace control box.

093

Control box defective

• Replace control box.

094

Control box defective

(EEPROM error)

• Replace control box.

095

Control box defective

• Replace control box.

096

Internal temperature sensor defective

• Replace control box or use external room temperature sensor.

097

Control box defective

• Replace control box.

098

Control box defective

• Replace control box.

099

Too many resets in sequence

Transistor error in control box

• Voltage short-term < 5 – 6 volt (for 12 volt) or < 7 – 8 volt (for 24 volt).

– In case of a voltage drop, check the fuses, the supply cables, the negative connections and the positive support point on the battery for corrosion and correct contact.


• Test control box with testing device.

– If OK –> check lead harness of the external components has been correctly laid and check for damage.

– If OK –> check lead harness for continuity.

– If OK –> replace control box.