AD83.70-W-6000D | Auxiliary heater (AHE) test of electrical system | 5.2.98 |
MODEL 625.1 /2, 655, 656, 657, 658, 659 with CODE (H08) Hot water auxiliary heater D 5 W
MODEL 650, 651, 652, 653, 654 with CODE (H08) Hot water auxiliary heater D 5 W
Auxiliary heater (AHE) diagnosis, previous knowledge | |||
| Auxiliary heater (AHE), location of components | ||
Auxiliary heater diagnostic tools | |||
| 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). | ||
| Cables, plug connections and fuses are included in the following tests. | ||
| Details of cable / cable colors, fuses and component installation locations in the following test instructions are valid only for vehicles with factory-fitted special equipment, auxiliary heater D5W . 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. Only heater unit components, control unit or operating unit(s) can be correctly diagnosed as fault sources. Faults in cabling etc. must be found manually using the relevant wiring diagram (e.g. from Eberspächer). | ||
a | On-board voltage 22.5-29.5V | ||
b | Connect Hand-Held Tester (HHT) | ||
Test | |||
1 | Generator charging voltage, testing electrical system of AHE | ||
2 | Battery voltage, testing electrical system of AHE | ||
3 | Auxiliary heater control unit overvoltage shutoff, testing electrical system of AHE | ||
4 | Auxiliary heater control unit undervoltage shutoff, testing electrical system of AHE | ||
5 | Open-circuit in metering pump, temperature-controlled cutout, control unit circuit, testing electrical system of AHE | ||
6 | Glow plug, testing electrical system of auxiliary heater | ||
7 | Diagnostic cable, testing electrical system of auxiliary heater | ||
8 | Combustion air blower, testing electrical system of AHE | ||
9 | Short-circuit to ground in combustion air blower, testing electrical system of AHE | ||
10 | Open-circuit in partial load relay circuit, testing electrical system of AHE | ||
11 | Short-circuit to ground in partial load relay, testing electrical system of AHE | ||
12 | Coolant circulation pump, testing electrical system of AHE | ||
13 | Fuel metering pump, testing electrical system of auxiliary heater | ||
14 | Flame monitor, testing electrical system of auxiliary heater | ||
15 | Open-circuit in temperature sensor circuit, testing electrical system of AHE | ||
16 | Open-circuit in flame monitor and temperature sensor circuit, testing electrical system of AHE | ||
17 | Short-circuit to ground in temperature sensor, testing electrical system of AHE | ||
18 | Open-circuit in flame monitor circuit, testing electrical system of AHE | ||
19 | Short-circuit to ground in flame monitor, testing electrical system of AHE | ||
20 | Timer supply voltage, testing electrical system of AHE | ||
21 | Timer, testing electrical system of AHE | ||
22 | Auxiliary heater control unit cables, testing electrical system of AHE | ||
23 | Auxiliary heater control unit, testing electrical system of AHE | ||
24 | Short-circuit in metering pump, testing electrical system of AHE | ||
25 | Short-circuit in control unit, testing electrical system of AHE | ||
26 | Control unit output glow pin, testing electrical system of AHE | ||
27 | Control unit output circulation pump, testing electrical system of AHE | ||
28 | Auxiliary heater relay, testing electrical system of AHE | ||
29 | Short-circuit in heater unit, testing electrical system of AHE | ||
30 | Timer output fuse carrier, testing electrical system of AHE |
Referenced documents
- ad0000w200003a Connecting hand-held tester (HHT), reading fault memory
- ad8370w200002c Auxiliary heater (AHE) diagnosis tools
- ad8370w2000e Auxiliary heater (AHE) diagnosis previous knowledge
- ad8370w600004b Auxiliary heater (AHE) test of electrical system diagnostic cable
- ad8370w600009b Auxiliary heater (AHE) test of electrical system heating plug
- ad8370w600010c Auxiliary heater (AHE) test of electrical system fuel metering pump
- ad8370w600013b Auxiliary heater (AHE) test of electrical system flame monitor
- ad8370w600018b AHE test of electrical system generator charge voltage
- ad8370w600019b AHE test of electrical system battery voltage
- ad8370w600020b AHE test of electrical system auxiliary heater control module overvoltage cutoff
- ad8370w600021b AHE test of electrical system auxiliary heater control module undervoltage cutoff
- ad8370w600022c AHE test of electrical system metering pump, temperature circuit breaker, control module open circuit
- ad8370w600024b AHE test of electrical system combustion air blower short to ground
- ad8370w600025b AHE test of electrical system part load relay open circuit
- ad8370w600026b AHE test of electrical system part load relay short to ground
- ad8370w600027a AHE test of electrical system coolant circulation pump
- ad8370w600028a AHE test of electrical system control module short circuit
- ad8370w600029c AHE test of electrical system temperature sensor open circuit
- ad8370w600030b AHE test of electrical system temperature sensor short to ground
- ad8370w600035c AHE test of electrical system auxiliary heater control module
- ad8370w600036c AHE test of electrical system flame monitor short to ground
- ad8370w600037c AHE test of electrical system flame monitor open circuit
- ad8370w600039c AHE test of electrical system timer supply voltage
- ad8370w600040c AHE test of electrical system timer
- ad8370w600042b AHE test of electrical system control unit output glow pin
- ad8370w600043b AHE test of electrical system control unit output circulation pump
- ad8370w600044b AHE test of electrical system timer output fuse carrier
- ad8370w600046c AHE test of electrical system combustion air blower
- ad8370w600047b AHE test of electrical system flame monitor and temperature sensor open circuit
- ad8370w600054b AHE test of electrical system auxiliary heater control module wiring
- ad8370w600060b AHE test of electrical system heater unit short circuit
- ad8370w600061c AHE test of electrical system metering pump short circuit
- ad8370w600068b AHE test of electrical system auxiliary heater relay
- gf8370w000303e Auxiliary heater (AHE), location of components