Audi Workshop Service and Repair Manuals > A4 Mk3 > Heating, ventilation, air conditioning system | Auxiliary heater | Aux. heater/heater booster | Checking electrical components of auxiliary heater

Checking glow plug for heaterQ9

Checking glow plug for heater -Q9-

l	Preparation for checking auxiliary heater components performed → Chapter

–	Unplug the connector -2- from the auxiliary heater.

–	Measure the resistance at the connector between contact “3” and the heater housing.

Specification:

∞ Ω

–	Measure the resistance at the connector between contacts “3” and “6”.

Specification:

Less than 1 Ω

Rated value:

0,42 - 0,63 Ω~(at 20 + / -2 °C)

Note

t	Resistances of less than 1 Ω can no longer be measured with the required accuracy using workshop equipment. This test can therefore only be used to detect major component damage.

t	If a voltage of 9 VDC is applied to the glow plug for heater -Q9-, the current input is between 9 and 20 A.

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