Volkswagen Golf Quiz
Auxiliary heater

Functional description

In this manual: Auxiliary heater
General body repairs, exterior — 230General body repairs, interior — 279General information, paint — 133Vechile- specific paint information — 27Heating, air conditioning — 156Auxiliary heater — 58Air conditioning system with refrigerant R134a — 1297- speed dual clutch gearbox 0CW — 544- cylinder injection engine(1.4 1 direct inction. turbocharger) — 182Fuel supply system - Petrol engines — 59Running gear, axles, steering — 221Brake system — 92Wheels and Tyres guide — 12Guide for using trailers — 11Wheels and Tyres Guide - General Information — 121Brake system (hybrid) — 73Electrical system — 326Communication — 65Electrical system, general information — 111
~3min read

The auxiliary and supplementary heater can be started by means of the remote control, the instant heating button or appropriate programming in the central monitor. The supplementary heater mode is started automatically by the vehicle electronics system once all the necessary preconditions have been met → Chapter. For vehicles with a high-voltage system and an auxiliary heater (installed as optional equipment) the control of the auxiliary heater or the high-voltage heater (PTC) -Z115- is coordinated between the operating unit of the Climatronic control unit -J255-, the battery regulation control unit -J840- and the control unit for high-voltage battery charging unit -J1050- (installed in the power and control electronics for electric drive -JX1-). The auxiliary heater (and the high-voltage heater (PTC) -Z115- on vehicles with a high-voltage system) is designed to heat the passenger compartment via the coolant circuit of the engine. Depending on the heat energy generated and emitted, there are various operating states of the auxiliary heater (full load, partial load, control interval). Initially, the fresh air blower -V2- and the combined glow plug with flame monitoring -Q8- are subjected to a functional test and then the glow plug with flame monitoring -Q8- goes through a preheating phase. The subsequent starting process depends on the coolant temperature, among other things, and can therefore vary in the amount of time it takes. The fuel is supplied, the glow plug with flame monitoring -Q8- is switched off in stages and the flame monitor is activated. After completion of the starting phase, the heater unit operates under full load and further load control (sparking mode, full load, partial load and controlled waiting period) takes place on the basis of the following coolant temperature thresholds.

Auxiliary and supplementary heater: auxiliary heater mode

  • Standard operating temperature: approx. 82 °C
  • Change to controlled waiting period: approx. 88 °C

Auxiliary and supplementary heater: supplementary heater mode

  • Standard operating temperature: approx. 82 °C
  • Change to controlled waiting period: approx. 88 °C
The reference resistance of the glow plug with flame monitoring -Q8- is automatically re-determined during the starting or run-on phase, depending on the unit. This is done to compensate for ageing-related changes. As a consequence of this calibrating procedure, processes that are affected can also require more time. After expiry of the maximum operating time of 60 min or after manual shutdown by means of the remote control or the instant heating button, the auxiliary and supplementary heater is switched off. The booster heater is switched off if at least one of the defined switch-on criteria is no longer met → Chapter.

After switch-off, operation of the metering pump -V54- is stopped immediately.

The combustion air blower -V6- and the glow plug with flame monitoring -Q8- continue to operate for a limited time in order to burn the remaining fuel still in the system and to cool the burner components. The run-on period of the heater can vary depending on the software version and load level at the time of switch-off.

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