DAF CF65, CF75, CF85 Series . Instruction - page 34

©

1-5

Hydronic 10 (ACH-EW) fault codes

HYDRONIC 10 (ACH-EW)

DAVIE XD diagnostics manual

6

1.3 EXPLANATORY NOTES TO FAULT CODES FOR HYDRONIC 10 (ACH-EW)

WITH ELECTRONIC UNIT D979

The below explanatory notes to fault codes apply

to the Hydronic 10 (ACH-EW) with the electronic

unit D979. The electronic unit can be identified by

the connector which is directly fitted in the unit.

Applicable to:

CF85 and XF95 (chassis number

 0E621373)

production date

2003-37

K101651

Fault code

Fault code description with possible cause

Symptom

0-0

Internal communication fault in ECU (D979) due
to:
-

defective ECU

-

Cab heater does not start or fails during
operation

0-1

Internal communication fault in ECU (D979) due
to:
-

defective ECU

-

Cab heater does not start or fails during
operation

1-0

Fault when starting ACH-EW, no flame is
detected within the start time. Flame sensor value
remains below 80ºC, voltage on pins 15 and 16 of
the 18-pin connector at the bottom of the ECU
<2.23 V due to:
-

no or insufficient supply of fuel

-

insufficient supply of inlet air

-

clogged exhaust

-

fouled or damaged burner

-

voltage too high or too low during glowing

-

Cab heater does not start. After 2 failed
starts the cab heater switches off and
generates a fault.

1-4

Too many starts without flame detection due to:
-

no or insufficient supply of fuel

-

insufficient supply of inlet air

-

clogged exhaust

-

fouled or damaged burner

-

voltage too high or too low during glowing

-

Cab heater shuts down after 10 failed starts
(20 start attempts) and the ECU will block

HYDRONIC 10 (ACH-EW)

1-6

©

Hydronic 10 (ACH-EW) fault codes

6

DAVIE XD diagnostics manual

2-0

Flame extinguishes repeatedly during operation
due to:
-

no or insufficient supply of fuel

-

insufficient supply of inlet air

-

undervoltage or overvoltage

-

excessively high flame sensor temperature

-

excessively high overheating sensor
temperature

-

defective combustion device

-

fouled or damaged burner

-

clogged or fouled exhaust

-

Cab heater fails or emits smoke and
supplies insufficient heat

3-1

Voltage (>30 V for at least 20 seconds) on pins
C2 and C3 of the ECU (D979) is too high due to:
-

excessive alternator/battery voltage

-

Cab heater fails during operation

3-2

Voltage (<20 V for at least 20 seconds) on pins
C2 and C3 of the ECU (D979) is too low due to:
-

insufficient supply voltage, for example
during starting

-

Cab heater fails during operation

4-0

Flame signalling when switching on. Flame
sensor value above 80ºC, despite 4 minutes'
cold-air ventilation; voltage on pins 15 and 16 of
the 18-pin connector at the bottom of the ECU
>2.23 V due to:
-

defective flame sensor

-

Cab heater does not start

5-1

Flame sensor short circuit on pins 15 and 16 of
the 18-pin connector at the bottom of the ECU

-

Cab heater does not start or fails during
operation

5-2

Open connection of flame sensor on pins 15 and
16 of the 18-pin connector at the bottom of the
ECU

-

Cab heater does not start or fails during
operation

6-1

Short circuit in coolant temperature sensor on
pins 14 and 18 of the 18-pin connector at the
bottom of the ECU

-

Cab heater does not start or fails during
operation

6-2

Open connection of coolant temperature sensor
on pins 14 and 18 of the 18-pin connector at the
bottom of the ECU

-

Cab heater does not start or fails during
operation

7-1

Short circuit in fuel metering pump (B122) on pins
C4 and C3 of the ECU

-

Cab heater does not start or fails during
operation

7-2

Open connection in fuel metering pump (B122)
on pins C4 and C3 of the ECU

-

Cab heater does not start or fails during
operation

8-3

Combustion device speed deviation due to:
-

defective combustion device

-

defective electronic unit (D979)

-

Cab heater fails with a delay of 60 seconds
during operation

9-1

Glow filament short circuit on pins 2 and 7 of the
18-pin connector at the bottom of the ECU

-

Cab heater does not start

9-2

Open connection of glow filament on pins 2 and 7
of the 18-pin connector at the bottom of the ECU

-

Cab heater does not start

10-0

Too fast a rise in coolant temperature due to:
-

poor flow of coolant

-

coolant shortage

-

use of intarder

-

Cab heater fails during operation

Fault code

Fault code description with possible cause

Symptom

©

1-7

Hydronic 10 (ACH-EW) fault codes

HYDRONIC 10 (ACH-EW)

DAVIE XD diagnostics manual

6

10-4

ACH-EW safety function switched on as a result
of:
-

too many overheatings

-

Cab heater fails. The ECU blocks after 3
failed starts.

11-1

Short circuit in coolant circulation pump on pins 3
and 6 of the 18-pin connector at the bottom of the
ECU

-

Cab heater does not start or fails during
operation

11-2

Open connection of coolant circulation pump on
pins 3 and 6 of the 18-pin connector at the bottom
of the ECU

-

Cab heater does not start or fails during
operation

13-1

Overheating sensor short circuit on pins 11 and
17 of the 18-pin connector at the bottom of the
ECU

-

Cab heater does not start or fails during
operation

13-2

Open connection of overheating sensor on pins
11 and 17 of the 18-pin connector at the bottom
of the ECU

-

Cab heater does not start or fails during
operation

13-3

Difference between value of overheating sensor
and value of coolant temperature sensor too large
due to:
-

poor flow of coolant

-

coolant shortage

-

use of intarder

-

Cab heater does not start or fails during
operation

15-1

Short circuit in wiring "signal ACH-EW on" to pin
A1 on ECU ALS-S (D911)

-

No interior detection alarm system (ALS-S)

Fault code

Fault code description with possible cause

Symptom

HYDRONIC 10 (ACH-EW)

1-8

©

Hydronic 10 (ACH-EW) fault codes

6

DAVIE XD diagnostics manual

Рассказать друзьям