WTT Fault Codes
From DISCO4.COM Knowledge Base
These are the fault codes reported by Webasto Thermo Test.
Depending on the version, the fault code may be reported in this format: 3Ah (i.e. ending in an 'h' instead of starting '0x'. To convert to the format given here, remove the 'h' and add '0x' at the start - so 3Ah is equivalent to 0x3A on this list.
List kindly supplied by alex_pescaru.
| Code (Hex) | Description |
|---|---|
| 0x01 | Defective control unit |
| 0x02 | No start |
| 0x03 | Flame failure |
| 0x04 | Supply voltage too high |
| 0x05 | Flame was detected prior to combustion |
| 0x06 | Heating unit overheated |
| 0x07 | Heating unit interlocked |
| 0x08 | Metering pump short circuit |
| 0x09 | Combustion air fan short circuit |
| 0x0A | Glow plug/flame monitor short circuit |
| 0x0B | Circulation pump short circuit |
| 0x0C | No communication to air condition |
| 0x0D | Green LED short circuit |
| 0x0E | Yellow LED short circuit |
| 0x0F | No configuration signal |
| 0x10 | Solenoid valve short circuit |
| 0x11 | ECU wrong coded |
| 0x12 | W-Bus communication failure |
| 0x13 | Vehicle fan relay short circuit |
| 0x14 | Temperature sensor short circuit |
| 0x15 | Combustion air fan blocked |
| 0x16 | Battery main switch short circuit |
| 0x17 | Invalid air flow reduction |
| 0x19 | Glow plug/electronic ignition short circuit |
| 0x1A | Flame sensor short circuit |
| 0x1B | Overheat short circuit |
| 0x1D | Solenoid valve shed test short circuit |
| 0x1E | Fuel sensor short circuit |
| 0x1F | Nozzle stock heating short circuit |
| 0x20 | Operation indicator short circuit |
| 0x21 | Flame indicator short circuit |
| 0x22 | Reference resistance wrong |
| 0x23 | Crash interlock activated |
| 0x24 | Car is almost out of fuel |
| 0x25 | Fuel pre heating short circuit |
| 0x26 | PCB temperature sensor short circuit |
| 0x27 | Ground contact to the ECU broken |
| 0x28 | Board net energy manager low power voltage |
| 0x29 | Fuel priming still not done |
| 0x2A | Error in the radio telegram |
| 0x2B | Telestart still not programmed |
| 0x2C | The pressure sensor has short circuit |
| 0x32 | No start from control idle period |
| 0x33 | Flame monitor signal invalid |
| 0x34 | Default values entered |
| 0x35 | EOL programming has not been carried out |
| 0x36 | Thermal fuse short circuit |
| 0x45 | Error relay box (short circuit/open circuit of heating relay) |
| 0x50 | User interface idle-Mode (no-communication) |
| 0x51 | User interface has communication fault |
| 0x52 | User interface send no defined operating mode |
| 0x53 | Heater fan status message negative |
| 0x54 | Heater fan status bus has short circuit to UB |
| 0x55 | Temperature water sensor failure |
| 0x56 | Temperature water sensor short circuit to UB |
| 0x57 | Overheating water temperature sensor |
| 0x58 | Overstepping water temperature sensor gradient |
| 0x59 | Overheating blow temperature sensor |
| 0x5A | Overstepping low temperature sensor gradient |
| 0x5B | Overheating printed circuit board temperature sensor |
| 0x5C | Overstepping printed circuit board temp sensor gradient |
| 0x5D | Cabin temperature sensor failure |
| 0x5E | Flame detector gradient failure |
| 0x5F | Emergency cooling |
| 0x81 | EOL checksum error |
| 0x82 | No start during test-run |
| 0x83 | Flame failure |
| 0x84 | Operating voltage too low |
| 0x85 | Flame was detected after combustion |
| 0x87 | Heater lock-out permanent |
| 0x88 | Fuel pump failure |
| 0x89 | Combustion air fan interruption |
| 0x8A | Glow plug / flame monitor interruption |
| 0x8B | Circulation pump interruption |
| 0x8D | Green LED interruption |
| 0x8E | Yellow LED interruption |
| 0x90 | Solenoid valve interruption |
| 0x91 | Control unit locked or coded as neutral |
| 0x92 | Command refresh failure |
| 0x94 | Temperature sensor interruption |
| 0x95 | Combustion air fan tight |
| 0x97 | Overheat sensor position wrong |
| 0x98 | Fault 152 (Power supply interruption) |
| 0x99 | Glow plug / electronic ignition unit interruption |
| 0x9A | Flame sensor interruption |
| 0x9B | Setpoint transmitter invalid |
| 0x9C | Intelligent undervoltage detection |
| 0x9D | Solenoid valve shed test interruption |
| 0x9E | Fuel sensor interruption |
| 0x9F | Nozzle stock heating interruption |
| 0xA0 | Operating indicator interruption |
| 0xA1 | Flame indicator interruption |
| 0xA5 | Fuel pre heating interruption |
| 0xA6 | PCB temperature sensor interruption |
| 0xA8 | Communication board net energy manager error |
| 0xAA | Send on W-Bus not succeed |
| 0xAB | Overheat sensor interruption |
| 0xAC | The pressure sensor failure |
| 0xB6 | Thermal fuse interrupted |
| 0xFF | Unknown error code |
