AD83.70-W-6000A | Auxiliary heater (AHE) test of electrical system | 3.12.97 |
MODEL 625.1 /2, 655, 656, 657, 658, 659 with CODE (H27) Hot water auxiliary heater DW 80
MODEL 650, 651, 652, 653, 654 with CODE (H27) Hot water auxiliary heater DW 80
Danger! | Risk of explosion due to fuel vapors, risk of poisoning from combustion gases and risk of injury from burning during or after heater operation | Do not put stationary heater or auxiliary heater or engine with heater booster into operation in confined spaces or in the vicinity of tank installations. Allow heater unit to cool down after operation and wear protective gloves. | |
Danger! | Risk of injury to skin and eyes through scalding by hot, pressurized coolant. Risk of poisoning through swallowing coolant. | Open cooling system only when coolant temperature is below 90°C. Slowly unscrew cap and allow the excess pressure to escape. Coolant should not be poured into drinking vessels. Wear protective gloves, protective clothing and protective glasses. | |
Auxiliary heater (AHE) diagnosis, previous knowledge | |||
Auxiliary heater (AHE) diagnosis function check using actual values | After repair check auxiliary heater using actual values 01 and 02 | ||
Connect Hand-Held Tester (HHT) | |||
| Cables, plug connections and fuses are included in the following tests. | ||
| Do not carry out measurements at contact points of plug connections with unsuitable equipment (test probes, wire ends etc.). Always use appropriate test cables from connection set (201 589 00 99 00). | ||
| If heater unit is retrofitted and a third party (e.g. drivers, customers) have made alterations / manipulations or non-specialist repairs have been made, the following test program may only be of limited use. The same applies to wiring diagram. | ||
| Corresponding test steps may be used for troubleshooting on retrofitted auxiliary heaters (e.g. this heater unit is not factory-fitted on GGVS vehicles). Only heater unit components, control unit or operating unit(s) can be correctly diagnosed as fault sources of faults. Faults in cabling etc. must be found manually using relevant wiring diagram (e.g. from Webasto). | ||
a | On-board voltage 22.5-29.5V | ||
Test | |||
1 | Fuel metering pump voltage supply, testing electrical system of AHE | ||
2 | Timer undervoltage, testing electrical system of AHE | ||
3 | Auxiliary heater control unit voltage supply, testing electrical system of AHE | ||
4 | Heater unit flame goes out with partial load, testing electrical system of AHE | ||
5 | Auxiliary heater control unit undervoltage, testing electrical system of AHE | ||
6 | Flame monitor, testing electrical system of auxiliary heater | ||
7 | Short-circuit to ground in flame monitor, testing electrical system of AHE | ||
8 | Short-circuit to ground in temperature sensor, testing electrical system of AHE | ||
9 | Fuel metering pump, testing electrical system of auxiliary heater | ||
10 | Short-circuit to ground in combustion air blower, testing electrical system of AHE | ||
11 | Open-circuit in flame monitor circuit, testing electrical system of AHE | ||
12 | Open-circuit in flame monitor and temperature sensor circuit, testing electrical system of AHE | ||
13 | Open-circuit in temperature sensor circuit, testing electrical system of AHE | ||
14 | Open-circuit in metering pump, temperature-controlled cutout, control unit circuit, testing electrical system of AHE | ||
15 | Open-circuit in metering pump, temperature-controlled cutout, control unit and combustion air blower circuit, testing electrical system of AHE | ||
16 | Open-circuit in combustion air blower circuit, testing electrical system of AHE | ||
17 | Glow pin, testing electrical system of AHE | ||
18 | Combustion air blower, testing electrical system of AHE | ||
19 | Heater unit flame goes out with full load, testing electrical system of AHE | ||
20 | Auxiliary heater control unit, testing electrical system of AHE | ||
21 | Timer supply voltage, testing electrical system of AHE | ||
22 | Timer, testing electrical system of AHE | ||
23 | Control unit output fuse carrier, testing electrical system of AHE | ||
24 | Control unit output glow pin, testing electrical system of AHE | ||
25 | Control unit output circulation pump, testing electrical system of AHE | ||
26 | Timer output fuse carrier, testing electrical system of AHE |
Referenced documents
- ad0000w200003a Connecting hand-held tester (HHT), reading fault memory
- ad8370w2000c Auxiliary heater (AHE) diagnosis previous knowledge
- ad8370w3006a Auxiliary heater (AHE) diagnosis operational check using actual values
- ad8370w600010a Auxiliary heater (AHE) test of electrical system fuel metering pump
- ad8370w600013a Auxiliary heater (AHE) test of electrical system flame monitor
- ad8370w600017a AHE test of electrical system auxiliary heater control module supply voltage
- ad8370w600022a AHE test of electrical system metering pump, temperature circuit breaker, control module open circuit
- ad8370w600024a AHE test of electrical system combustion air blower short to ground
- ad8370w600029a AHE test of electrical system temperature sensor open circuit
- ad8370w600030a AHE test of electrical system temperature sensor short to ground
- ad8370w600035a AHE test of electrical system auxiliary heater control module
- ad8370w600036a AHE test of electrical system flame monitor short to ground
- ad8370w600037a AHE test of electrical system flame monitor open circuit
- ad8370w600038a AHE test of electrical system glow pin
- ad8370w600039a AHE test of electrical system timer supply voltage
- ad8370w600040a AHE test of electrical system timer
- ad8370w600041a AHE test of electrical system control unit output fuse carrier
- ad8370w600042a AHE test of electrical system control unit output glow pin
- ad8370w600043a AHE test of electrical system control unit output circulation pump
- ad8370w600044a AHE test of electrical system timer output fuse carrier
- ad8370w600045a AHE test of electrical system combustion air blower open circuit
- ad8370w600046a AHE test of electrical system combustion air blower
- ad8370w600047a AHE test of electrical system flame monitor and temperature sensor open circuit
- ad8370w600048a AHE test of electrical system metering pump, temperature circuit breaker, control module and combustion air blower open circuit
- ad8370w600049a AHE test of electrical system heater unit flame cuts out at full load
- ad8370w600050a AHE test of electrical system heater unit flame cuts out at part load
- ad8370w600051a AHE test of electrical system fuel metering pump supply voltage
- ad8370w600052a AHE test of electrical system auxiliary heater control module undervoltage
- ad8370w600053a AHE test of electrical system timer undervoltage
- as2000z000101a Risk of injury to skin and eyes suffering scalding from contact with hot coolantspray. Risk of poisoning from swallowing coolant.
- as8370z000201a Risk of explosion caused by fuel vapors igniting, risk of poisoning caused by inhaling combustible gases and risk of injury caused by burns during and after operation of heater unit