AD83.70-W-6000-35A | AHE test of electrical system auxiliary heater control module |
| Scope of test | Measuring instrument/ Test connection | Operation/Requirement | Specified value | Possible cause/Remedy | ||
1.0 | Control unit (Z14) Voltage supply |
B4 | Z14 |
A2 | Ignition: ON Heater unit: OFF Connect measuring instrument to plug A and plug B from control unit (behind timer). Heater unit: ON Observe voltage up to 60s after switching on heater unit. | Value 18–24 V (after approx. 30 s): 1.1 Value approx. 0 V (after approx. 30 s) and fault code re-appears: Replace control unit (Z14). | |
1.1 | Control unit (Z14) Voltage supply |
B4 | Z14 |
A2 | Ignition: ON Heater unit: OFF Connect measuring instrument to plug A and plug B from control unit (behind timer). Disconnect plug connection A from control unit, observing measuring instrument. | Value approx. 0 V: Replace control unit (Z14) on trial. Value > 18 V: If voltage falls to approx. 0 V after switching off ignition, short-circuit in cable from control unit to heater unit to terminal 15. If voltage is measured after ignition switched off, cable-short to terminal 30. | |