Removing and installing auxiliary heater components — AUDI

Cap
Bolt
Series resistor -N6
Removing and installing => Page
82-52

Bracket
Rubber grommet
Connection cable
For glow plug

Glow plug -Q6
Removing and installing => Page
82-55

Flame detector -G64
Removing and installing => Page
82-54

Screw
O-ring seal
Replace

O-ring seal
Replace

Combustion air blower -V6
Removing and installing => Page
82-53

Screws
Cable tie
Clip
For attaching recirculation pump

Recirculation pump -V55
Removing and installing => Page
82-61
Attach to bracket only after installing auxiliary heater

Shaped seal
Replace
Install with open side facing auxiliary heater => Page
82-61

Auxiliary heater
Dismantling and assembling =>Page
82-62

O-ring seal
Replace

Temperature sensor -G18
Removing and installing => Page
82-57
Testing resistance => Page
82-58

O- ring seal
Replace

Overheating cut-out -S24
Removing and installing => Page
82-59
Switching on => Page
82-60
If fuse has tripped:

=> Binder "Fault finding heater, air conditioner"

Adhesive strap
For wrapping around cables between flexible corrugated tube and 12-pin connector housing

Top part of 12-pin connector housing

Bottom part of 12-pin connector housing
Removing and installing individual contacts => Fig.
1
Connection diagram => Fig.
2

Flexible corrugated tube
Slotted

Rubber grommet

Fig.1
Removing and installing individual plug contacts from 12-pin connector housing

Removal:

Remove auxiliary heater => Page
82-18
.
Unwrap adhesive tape from end of flexible corrugated tube up to connector housing.
Carefully lever off 12-pin connector housing using a screwdriver.

Installation:

Wrap adhesive tape around cables between 12-pin connector housing and flexible corrugated tube after assembling.

Fig.2
Connection diagram for 12-pin

connector housing

1 -
Flame detector -G64
2 -
Temperature sensor -G18
3 -
Overheating cut-out -S24 (with on switch)
4 -
12-pin connector housing
5 -
Recirculation pump -V55
6 -
Combustion air blower -V6
7 -
Series resistor -N6

Cable colours
bl · = blue · li · = lilac · ws · = white
br · = brown · or · = orange
gn · = green · ro · = red

Notes:

If contacts are inserted incorrectly, this will cause operational problems.
If overheating cut-out has tripped:

Check whether coolant circuit is bled => Page
82-20
.
Check operation of auxiliary heater:

=> Binder "Fault finding heater, air conditioner"

Removing and installing series resistor -N6

Removal:

Remove auxiliary heater => Page
82-18
.
Remove corresponding electrical connections from 12-pin connector housing => Fig.
82-50
.

Remove 2 screws -A-.
Remove old heat conducting paste on contact surface -C- between resistor and bracket after removing series resistor -B-.
Coat contact surface with new heat conducting paste (available through electronics trade).
Resistance 3.9 ± 0.1 ω

Installation:

Install in reverse order, paying attention to the following:

If a resistor with short connection cable is supplied as a replacement part, unsolder this cable at series resistor and solder on the long connection cable of faulty series resistor.

Removing and installing combustion air blower -V6

Removal:

Remove auxiliary heater => Page
82-18
.
Remove corresponding electrical connections from 12-pin connector housing => Fig.
82-50
.

Remove 2 screws -B-.

Installation:

Insert O-ring seal -A-into groove.
Note correct contact assignment in 12-pin connector housing => Fig.
82-51
.

Removing and installing flame detector -G64

Removal:

Remove auxiliary heater => Page
82-18
.
Remove corresponding electrical connections from 12-pin connector housing => Fig.
82-50
.

Remove screw -A-.
Pull flame detector -C- out of auxiliary heater at clamp.

Installation:

Insert O-ring -B- onto flame detector.
Dimension x = 10 mm

Note correct contact assignment in 12-pin connector housing => Fig.
82-51
.
Ensure that pressure compensating hole -D- is not blocked.

Removing and installing glow plug -Q6

Removal:

Remove auxiliary heater => Page
82-18
.

Unplug glow plug connector -B-.
Remove glow plug -A- (30 Nm).
Remove any coke deposits on glow plug coil -C- by cleaning carefully.
Inspect glow plug:
Windings of glow plug coil -C- must not be touched (risk of short circuit)
Current consumption at a voltage of 12 V is 18... 22 A

Inspect glow plug connector -B- for signs of damage and tight fitting.

If glow plug is faulty or coked:

Take off cover -A-.
Install a new set of seals -B- (fuel non-woven disc, spacer and seals) => Page
82-67
.

Note:

If starting problems are encountered at low outside temperatures (auxiliary heater does not start until after a repeat start) although quantity of fuel pumped and CO2- concentration in exhaust is OK, check wiring between second batter -A1, auxiliary heater control unit -J162 and glow plug -Q6 for contact resistance:

=> "Current flow diagrams, Electrical fault finding and fitting locations" binder

Installation:

Screw in glow plug to 30 Nm.

Note:

When installing, pay particular attention to ensuring that glow coils do not touch any other components (risk of short circuit).

Removing and installing temperature sensor -G18

Removal:

Remove auxiliary heater => Page
82-18
.
Remove corresponding electrical connections from 12-pin connector housing => Fig.
82-50
.

Unscrew temperature sensor -B-.

Installation:

Insert O-ring seal -A-into groove.

Note:

Moisten O-ring seal with coolant.

Screw in temperature sensor to 0.5 Nm.
Note correct contact assignment in 12-pin connector housing => Fig.
82-51
.

Testing resistance of temperature sensor -G18

A -
Resistance (ω)
B -
Coolant temperature (oC)
C -
Resistance of temperature sensor

Notes:

Test current when measuring resistance should not be more than 1mA
Connection diagram for 12-pin connector housing => Fig.
82-51
.

Removing and installing overheating cut-out -S24

Removal:

Remove auxiliary heater => Page
82-18
.
Remove corresponding electrical connections from 12-pin connector housing => Fig.
82-50
.
Pull off rubber grommet.
Unscrew overheating cut-out -B-.

Installation:

Clean contact surface -C- on heat exchanger in housing.
Overheating cut-out should make proper contact all round.

Insert O-ring seal -A- into groove and moisten with coolant.
Screw in overheating cut-out -B- to 1.5 Nm.

Carefully pull rubber grommet over overheating cut-out.
Fit rubber grommet so that cables do not prevent overheating cut-out from tripping.
Button -D- should not be obstructed

Note correct contact assignment in 12-pin connector housing => Fig.
82-51
.

Switching on overheating cut-out

Remove air inlet grille and front bumper:

=> General body repairs; Repair group 63; Front bumper
General body repairs
Front bumper

Remove left fog light:

=> Electrical system; Repair group 94; Servicing headlights; Servicing headlights Audi 100 ä 05.94
Electrical system
Servicing headlights
Servicing headlights Audi 100 ä 05.94

To switch on overheating cut-out, insert hand through bumper and press vertically down on button -A-.

Note:

Carry out operational check if overheating cut-out has tripped:

=> Binder "Fault finding heater, air conditioner"

Removing and installing circulation pump -V55

Removal:

Remove auxiliary heater => Page
82-18
.
Remove corresponding electrical connections from 12-pin connector housing => Fig.
82-50
.

Slacken clip -A-.

Installation:

Fit shaped seal -B- onto circulation pump.
Installation position: open side faces auxiliary heater

Push on clip -A- in direction of arrow as far as stop.
Note correct contact assignment in 12-pin connector housing => Fig.
82-51
.
Inspect installation position of circulation pump:
Circulation pump must not be touching bracket, align bracket, if necessary