Incorrect jumpstart advice needed.

[427mikeb]

Skoda Superb 2014 1.8TSI ( Based in Essex) 

Hi, I could really do with some help, I’ve got myself into a major mess & unsure which direction to go in.

Yes, I’m kicking myself & calling myself all the names under the sun & I still can’t believe what I’ve done.  I’ve accidentally tried jumping the car with the jump leads the wrong way round. The ignition is now dead screen. Some parts of the electrics are ok, central locking, interior lights etc.

 I’ve checked all the fuses in the engine bay & the interior ones on the side of the dash & all are good. I’m assuming I’ve fried some critical electronic modules. The ECU or something else or lots of things.
Does anyone have any advice for a way forward to diagnose? Do I need an auto electrician or a particular type of garage or is it completely wrecked & beyond help?

  Many thanks.  Mike 

[J.R.]

You are very unlikely to have fried any modules, the most basic thing even on the simplest of circuits is to protect against reverse polarity connection.

 

There may be other fuses that you are unaware of or even fusible links within some of the major unfused cables usually the ignition system, others with access to circuit diagrams will be able to advise you.

[427mikeb]

Thanks, that sounds slightly more positive than I’m feeling at the moment. 

[chimaera]

Start by identifying which systems are working and which are not: go through every electrical feature or function in the car. From there you can start looking at all fuses and relays associated with them. Post the list of what's working and not working here and we can guide you.

[427mikeb]

Ok thanks. It seems all I have working is

The central locking

The interior courtesy light when I open the door

The headlamp LED strips & rear lights if I select sidelights on the control knob

The boot opening solenoid

Nothing else

 

Mike

Edited 23 July, 2023 by 427mikeb

[chimaera]

Ok, sounds like the BCM is ok. What trim level do you have? Any optional extras? This will help figure out what other ECUs are fitted and where to look for faults.

[427mikeb]

Update.

it’s an Elegance, so electric heated seats, winter pack, solar panel sunroof.

 

 Have calmed down after my head exploded & the useful info from here that all may not be lost. Have gone through all the fuses again in a more methodical way & in the engine fuse box found F8 15 amp Radio blown. Have replaced & everything has returned including engine start. So F8 must do a bit more than radio.

Im now left with some yellow warning lights on the dash

1. power steering / steering lock KESSY system)

2. Traction control system / electronic stability control

3. Tyre pressure ( flashing & will not reset)

 

I tried disconnecting the battery to see if that would reboot something, but to no avail. Would that need resetting with an OBD scanner or will this be a module common to all?

Compared to where I was a few hrs ago I’m feeling a lot happier.

 

 

[chimaera]

Those lights usually go on when batteey power is lost because the steering angle sensor loses its calibration. Start the engine then turn the wheel fully from lock to lock and they should go out.

[Snapper1725]

3 hours ago, 427mikeb said:

Update.

it’s an Elegance, so electric heated seats, winter pack, solar panel sunroof.

 

 Have calmed down after my head exploded & the useful info from here that all may not be lost. Have gone through all the fuses again in a more methodical way & in the engine fuse box found F8 15 amp Radio blown. Have replaced & everything has returned including engine start. So F8 must do a bit more than radio.

Im now left with some yellow warning lights on the dash

1. power steering / steering lock KESSY system)

2. Traction control system / electronic stability control

3. Tyre pressure ( flashing & will not reset)

 

I tried disconnecting the battery to see if that would reboot something, but to no avail. Would that need resetting with an OBD scanner or will this be a module common to all?

Compared to where I was a few hrs ago I’m feeling a lot happier.

 

 

Them faults normally clear within a short distance of driving 

[427mikeb]

Ok, thank you gents, suggestions much appreciated. 
The steering lock to lock cleared a couple & then a 300yd drive cleared the tyre pressure fault.

I feel like I’ve dodged a bullet today, the lows & highs of stupidity.

Still unsure why Skoda have a protective cover on the battery  -ve post whilst every other car I’ve owned it’s the +ve that’s covered. I’ll pay more attention next time. 

[Nigel_S]

I wondered that too! I expected + to have the protection and not - 

[3T51704x4]

On 23/07/2023 at 18:36, 427mikeb said:

Still unsure why Skoda have a protective cover on the battery  -ve post whilst every other car I’ve owned it’s the +ve that’s covered. I’ll pay more attention next time. 

Hi, it is to stop you putting the negative on the negative battery post, (look at the messaging closely, shows NOT to place the jump lead at the battery post) bypassing the battery manager. By using the provided body earth, the current being introduced goes through the battery manager (we call it word 61) later cars has it as a slave to the gateway (word 19). Lots of very useful battery info in the measured value blocks if you know what to look for.

Changed a few of these units where they fail if it gets spiked. communicates via LIN Bus.