AD83.70-W-6000-13B | Auxiliary heater (AHE) test of electrical system flame monitor |
| Scope of test | Measuring instrument/ Test connection | Operation/Requirement | Specified value | Possible cause/Remedy | ||
1.0 | Flame sensor Internal resistance |
14/8 | G |
14/9 | Ignition: OFF Heater unit: OFF Allow engine and heater unit to cool down if necessary. Open flap on air recirculation box. Carry out measurement at 14-pin plug connection G on vehicle blower. | 1.0–1.7 kΩ | Value in order: Erase fault code, if fault code re-occurs: 1.1 Value <1 kΩ or >2 kΩ with cold heater unit (approx. 20 °C): Replace flame sensor on trial. |
1.1 | Flame sensor Cables |
14/8 A5 | G Z13 |
14/9 A4 | Ignition: OFF Heater unit: OFF Connect short-circuit bridge to 14-pin plug connection G on vehicle blower. Disconnect 13-pin plug connection A on control unit. | Value > 20 Ω: Check plug connection FF8 under electrical compartment, plug connection G in air recirculation box (14-pin), plug A on control unit and plug connection K on unit mount for corrosion / transition resistance or loose contact. Value < 5 Ω: Replace control unit (Z13) on trial. | |