Dismantling and assembling heater unit -D3W- — VW
Dismantling and assembling heater unit -D3W- on VW: factory workshop procedure. Full factory text, tools and checks.
Workshop procedure for VW — the factory write-up, straight from real workshop data.
📋 Procedure
ℹ️ Torque figures below come verbatim from workshop data — always cross-check against your vehicle's factory manual before final tightening.
Water jacket cover
Bolt M5x12
Heat exchanger
Clean inside and outside with brass wire brush (spark plug brush)
Observe installation position
=> Fig.
4
O-ring
Renew
Lubricate when installing
Gasket
Always renew after dismantling
Combustion chamber with flame tube
Clean inside and outside with brass wire brush (spark plug brush)
Combustion air blower cover
Bolt M5x22
Bolt M4x10
Socket head screw M5x65
6 Nm
Socket head screw M5x16
6 Nm
Control unit -J162-
Removing => Fig.
1
Checking
=> Fault finding; Heating, air conditioning binder 2
Combustion air blower -V6-
Do not dismantle further
Checking
=> Fault finding; Heating, air conditioning binder 2
Cover
Rubber grommet
Gasket
Always renew after dismantling
Flame detector -G64-
Removing => Fig.
18
Checking
=> Fault finding; Heating, air conditioning binder 2
Glow plug for heater -Q9-
Removing => Fig.
2
Clean pin with brass wire brush (spark plug brush)
6 Nm
Checking
=> Fault finding; Heating, air conditioning binder 2
Water jacket
Clean inside and outside with brass wire brush (spark plug brush)
Overheating sensor -G189-
Checking
=> Fault finding; Heating, air conditioning binder 2
Temperature sensor -G18-
Checking
=> Fault finding; Heating, air conditioning binder 2
Spring
Do not bend further
Renew if damaged
Bolt M5x16
Fig.1
Removing control unit -J162-
Removing radiator grille:
=> General body repairs; Repair group 66; Servicing radiator grille; Removing radiator grille
General body repairs
Servicing radiator grille
Removing radiator grille
Fold radiator and lock carrier out forwards.
Pull 8 pin connector off -T8-.
Loosen both cross head screws -2- from combustion air blower cover.
Remove cross head screws -3- and socket head bolts -4- and -5-.
Lift control unit -1-.
Pull 10 pin connector off.
Fig.2
Removing glow plug for heater -Q9-
Remove control unit=>Fig.
1
.
Remove cover =>Page
82-177
; item
14
.
Disconnect glow plug wiring.
Remove glow plug -1-.
Fig.3
Removing flame monitor -G64-
Remove control unit=>Fig.
1
.
Remove cover =>Page
82-177
, item
14
.
Pull flame monitor wiring out of 10 pin connector -2-.
Unbolt flame monitor -1-.
Fig.4
Heat exchanger installation position
Insert heat exchanger -2- into water jacket -1- until centering -arrows- engage.
Push heat exchanger tightly into seating.
TorqFix answers live for your specific car — tell it the engine code and it serves the matching sequence, torque figures and wiring for that exact variant.
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Who makes these pages, and how
TorqFix was built by a mechanic — after a 2,700 km drive with five roadside repairs that no diagnostic tool could explain.
The figures on this page come from manufacturer workshop documentation and are shown as they are. The page is assembled automatically from that data — it is not written by an AI. The AI works in the chat, where it answers for your specific car. It writes nothing here.
Variants of the same model differ. Cross-check torque against the factory manual for your engine before final tightening.
Seen a figure that does not match your manual? Write to us — we correct it and note when. support@torqfix.com
The story behind TorqFix →Workshop data on this page last updated 20 Sep 2026.