Typical Vauxhall Astra components

13

Positioned between the left-hand inner wing and the battery is the underbonnet fuse and relay box assembly. Beneath this is the car’s body control unit. It’s essential that moisture is kept at bay in this area, so always ensure that the cover is correctly fitted.

14

The focus of attention here is the clamp sensor assembly that surrounds the main negative (earth/ground) cable running from the battery to an earth connection point on the vehicle body. Check the cable and all connections.

15

There are two vital earth connection points on the left-hand suspension tower. Ensure that the connections are clean and in good condition, and also that they’re firmly attached. If in any doubt, dismantle, clean and reassemble the connections, applying silicone protectant.

16

Located within the depths of the engine bay and beneath the battery is this main loom connection assembly. Make sure that the cables are in good condition, with the connections free from moisture and corrosion.

17

Seen here is the Delphi ignition coil set-up, normally concealed beneath a plastic cover at the top of the engine. Problems can arise here but, fortunately, this area is readily accessible by removing the cover.

18

The diagnostic socket is located at the bottom of the fascia assembly, on the right-hand side, and is seen here with the cable for the Verus Pro unit plugged in. Make sure the plug is correctly/fully inserted.

19

Live data regarding the MAP sensor is displayed in this screenshot. Any sensor problems should show up in the signal.