Checking the preheating device (Audi A4 B8)

Table of contents: Glow plugs, Hall sensors, engine… ↓ Removal and installation of the Hall… ↓ Removal and installation the engine… ↓

The control unit for automatic glow plug timing "J179" is located in the relay and fuse box in the switch. block in the water drainage box.

A. Automatic glow plug timing control unit "J179"

The pre-heating system is controlled by the J79 glow plug timing control unit. The J179 glow plug timing control unit is capable of self-diagnostics. If the pre-heating device fails, an error record is stored in the engine control unit. System check. the pre-heating function is described in the "Guided Troubleshooting" section. To achieve the quick-start function, the electronically controlled glow plugs are connected to a separate glow plug control unit. Each glow plug is controlled and diagnosed individually.

Glow plugs, Hall sensors, engine speed sensor

1. Hall sensor "G40".
2. Bolt: 9 Nm.
3. Glow plug: glow plug 1 "Q10", glow plug 2 "Q11", glow plug 3 "Q12", glow plug 4 "Q13"; 17 Nm.
4. Electrical plug connection: for glow plug.
5. Bolt: 4.5 Nm.
6. Engine speed sensor "G28".
7. Sealing flange on the gearbox side: with shaft seal.
8. Gear of the engine speed sensor "G28".

Removal and installation of the Hall sensor "G40"

Remove the timing belt from the idler pulley and high pressure pump.

Remove plug connection "2" from the holder and disconnect it. "Pos. 1" should not be taken into account.

Unscrew the Hall sensor "G40" "arrow".

Remove the spacers with a screwdriver and remove the repair opening trim "arrows". Remove the Hall sensor "G40" from the cylinder head and route its connector through the repair opening in the toothed belt protective cover.

Installation

Installation in reverse order. Close the repair hole in the timing belt protective lining with a rubber plug. Install the timing belt and adjust the timing phases.

Removal and installation the engine speed sensor "G28"

Remove the radiator pump system. eGR "V400". Disconnect plug connection "1" of engine speed sensor "G28" using mounting. tool "T10118". Release the wire. Remove the bolt from the engine speed sensor "G28".