I went round another members place last night to help him bleed the brakes for the Castle Combe track day and there are various problems with his VRS, most of which seem electrical, the car is drivable but he wants to sort the issues out and we don't know where to start so any suggestions would be welcome.

Mechanical issues:

1. Rear offside brake bleed nipple screw is seized. We didn't want to force it in case something snapped but looks like this is going to mean a new caliper?

2. Car was remapped last year but recently seems to have lost urgency at low revs. There were no stored fault codes but when I tried to do boost and torque measurements later in the evening the OBD port wasn't playing ball (see below)

3. DV is rattling - thought this was causing issue 2 above so have tightened the spring and changed it to fully recirculating (its a Split-R), this has stopped the rattling but not cured issue 2.

Electrical issues:

4. Windows would not auto close with the key in the lock. We disconnected the battery for an hour then reset the locked position and these are now working fine but something must have caused this in the first place and we think it might be related to the below

5. Crackling from rear tweeter / reversing sensor speaker. This occurs after ignition is switched to position 2 or all the way on. It got worse every time I tried to use the OBD port (see below) I unplugged the tweeter from the rear speaker and we still heard the crackling so thinking it must be the reversing speaker not the tweeter

6. OBD port is borked. It worked fine at the start of the evening but after the battery disconnect when I plugged the Liquid Gauge back in it wouldn't communicate with the car and kept saying "comms error".

7. Stereo is saying SAFE after the battery disconnect. It should only say this for 30 secs or so and then let you input the Keycode but it's not doing so

We're wondering whether the electrical issues are something like a fault with a common earth point?

Thanks, sorry for the essay

The crackling you have described and electrical items not retaining info does point to a poor earth. It may have worked loose or be corroded so well worth checking that.

Edited 20 April, 201016 yr by Col-vRS

I think he's going to check behind the B-pillar trim and the rear passenger door today for an earthing point for the reversing speaker and/or tweeter. Does anyone know if these share an earthing point with the OBD port?

Edited 20 April, 201016 yr by chicken_eyebrow

Mechanical issues:

1. Rear offside brake bleed nipple screw is seized. We didn't want to force it in case something snapped but looks like this is going to mean a new caliper?

You could possibly try applying some heat to the nipple and see if the caliper expands ever so slightly, thus breaking the corrosion/bonding which has taken place? Otherwise maybe some plus-gas on it and hope for the best.

Edited 20 April, 201016 yr by mbames

plently of shock n release on the rear bleed nipple, over several days, then heat to try to release, prob is without releasing you cant bleed full system properly.

Gonna vag check it tomorrow..........see what comes up!

Gonna vag check it tomorrow..........see what comes up!

That's if you can get a response from the OBD port :S

yup thats true!

hmmm yup no response from obd port, need to test for power to the port and chck to see if ay signal on the k-line feed.