Fault codes DFF LF45IV, LF55IV, CF65IV, CF75 IV, CF85 IV, XF95, XF105 – TROUBLESHOOTING COMMENTS for HYDRONIC 10 (ACH-EW) with electronic unit D901
The fault codes for the HYDRONIC 10 (ACH-EW) system with electronic unit D901 are explained below. This electronic unit can be recognised by the built-in cable with plug.
Please note
Applies to DAF XF95 with chassis numbers up to 0E621373, issued before July 2003.
| Codemalfunction | Fault code description and possible causes | Symptoms |
| 0-0 | Internal communication failures in the electronic control unit (D901) due to the electronic control unit | -Cabin heater does not run or runs erratically |
| 0-1 | Internal communication failures in the electronic control unit (D901) due to the electronic control unit | -Cabin heater does not run or runs erratically |
| 1-0 | Launch failure ACH-EW, the flame is not detected during startup. Flame sensor value remains below 80° c voltage at pins 10 and 12 18-pin connector at the bottom of the electroniccontrol unit below the 2.23 in:-The absence or insufficient fuel supply-Insufficient air supply-A clogged exhaust-Pollution or damage the igniter-Too high or too low voltage spark | -Cabin heater does not start. After two failed launches of the cabin heater shuts down and throws a fault code. |
| 1-4 | Too many runs without flame detection:-The absence or insufficient fuel supply-Insufficient air supply-A clogged exhaust-Pollution or damage the igniter-Too high or too low voltage spark | -Cabin heater shuts down after 10 unsuccessful launches (20 launch attempts) and the electronic control unit is blocked |
| 2-0 | Flame goes out often during work:-The absence or insufficient fuel supply-Insufficient air supply-Low or high voltage-Excessively high temperature flame sensor-Excessively high temperature sensor overheating-Faulty combustion device-Pollution or damage the igniter-Clogging or contamination of exhaust | -Cabin heater does not work or works, highlighting the lack of heat |
| 3-1 | Too high voltage (above 30 in over 20 seconds) on the findings of the A5 and Jsb electronic control unit (D901) due to excessive voltage generator/accumulatorbattery | -CAB heater malfunction |
| 3-2 | Too low voltage (below 20 in over 20 seconds) on the findings of the A5 and Jsb electronic control unit (D901) due to insufficient supply, such as during engine start | -CAB heater malfunction |
| 4-0 | Alarm flame when turned on. Flame sensor value above 80° c, despite the four-minute ventilation cold air; voltage at pins 10 and 12 18-pin connector at the bottom of the electronic control unit above 2.23 in flame sensor malfunction as a result. | -Cabin heater won’t start |
| 5-1 | Flame sensor short circuit at pins 10 and 12 18-pin connector at the bottom of the electronic control unit | -Cabin heater does not run or runs erratically |
| 5-2 | Flame sensor open circuit on the findings of the 10 and 12 18-pin connector at the bottom of the electronic control unit | -Cabin heater does not run or runs erratically |
| 6-1 | A short circuit in the engine coolant temperature sensoron the findings of the 9 and 11 18-pin connector at the bottom of the electronic control unit | -Cabin heater does not run or runs erratically |
| 6-2 | Open circuit coolant temperature sensor on the findings9 and 11 18-pin connector at the bottom of the electronic control unit | -Cabin heater does not run or runs erratically |
| 7-1 | Shorted fuel pump module with level sensor (122) on the findings of the A1 and A2 electronic control unit | -Cabin heater does not run or runs erratically |
| 7-2 | Open circuit fuel pump module with level sensor (122) on the findings of the A1 and A2 electronic control unit | -Cabin heater does not run or runs erratically |
| 8-3 | Deviation speed combustion devices:-Faulty combustion devices-Faulty electronic unit (D901) | -Cabin heater during the work refuses delay in 60 seconds |
| 9-1 | Shorted filament on the findings of the 3 and 4 18-pin connector at the bottom of the electronic control unit | -Cabin heater won’t start |
| 9-2 | Open circuit of filament on the findings of the 3 and 4 18-pin connector at the bottom of the electronic control unit | -Cabin heater won’t start |
| 10-0 | Too rapid growth of coolant temperature:-Poor fluid flow-Lack of coolant-Use intardera | -Cabin heater refuse during operation |
| 10-4 | Included safety function ACH-EW as a result of too many overheats | -Cabin heater not working. The electronic control unit is locked after three failed launches |
| 11-1 | Short circuit the coolant circulation pump on the findings of 6 and 7 18-pin connector at the bottom of the electronic control unit | -Cabin heater does not run or runs erratically |
| 11-2 | Open circuit the coolant circulation pump on the findings6 and 7 18-pin connector at the bottom of the electronic control unit | -Cabin heater does not run or runs erratically |
| 13-1 | Short circuit sensor overheating on the findings of 5 and 8 18-pin connector at the bottom of the electronic control unit | -Cabin heater does not run or runs erratically |
| 13-2 | Open circuit sensor overheating on the findings of 5 and 8 18-pin connector at the bottom of the electronic control unit | -Cabin heater does not run or runs erratically |
| 13-3 | Too much difference between the values in the sensor overheating and coolant temperature sensor:-Poor fluid flow-Lack of coolant-Use intardera | -Cabin heater does not run or runs erratically |
| 15-1 | Short circuit in wiring “signal at the output” ACHEW A9 ALS-electronic control unit S (D911) | -No detection alarm systems (ALS-S) |
