172 electrical gremlins, won't turn over

[Le Baguette]

Hello, new to the forum and to these cars as well. A bit sad that my first 'contribution' had to be asking for help though..

Got myself a 2003 172 last week with ~44000 miles and it had been working flawlessly but today after swapping the stereo head unit, removing the stock CD changer and the hazard switch due to it being broken, the car wouldn't start!

Central locking does NOT work. Neither do the headlights but AC turns on just fine together with working brake and fog lights.
I get a solid STOP and a flashing SERV light on the dash and when turning the key absolutely nothing happens.

Battery isn't drained, shows close to 13 volts.
I've tried my spare key but problem persists.
Could it be a starter relay? Seems odd the central locking is dead too?

Worth mentioning is I did fiddle with the air box and accidentally dropped a screw I have yet to find but I doubt that could have anything to do with it?

I did search and been googling for hours but seems no one has a similar issue where even the spare key won't help or that the battery's in good condition as in this case.

Any help is much appreciated.

Aleks

 

[Le Baguette]

Turned out the faulty central locking was due to a burnt 5 amp fuse...

Checked the rest of the fuses and the relays by the battery to no avail.

Where are the ground points? I know there is one by the gearbox inside the front left tyre inner-fender that I have yet to look at but what else is there?

 

[Mr R.]

By the head light on the N/S.

 

[Carlv8415]

Turned out the faulty central locking was due to a burnt 5 amp fuse...

Checked the rest of the fuses and the relays by the battery to no avail.

Where are the ground points? I know there is one by the gearbox inside the front left tyre inner-fender that I have yet to look at but what else is there?

Just about the say check the 5amp sure inside the passenger door panel fuse box. Blew it when changing the stereo on the 182. That 5amp fuse controls ECU and UCH power so nothing works lol

 

[Le Baguette]

By the head light on the N/S.

Cheers!
I guess that's the one by the gearbox inside the wheel? I was told you need to remove the front left wheel to get to it, correct?

Just about the say check the 5amp sure inside the passenger door panel fuse box. Blew it when changing the stereo on the 182. That 5amp fuse controls ECU and UCH power so nothing works lol

Did I feel stupid when I noticed!

Car still won't start though. Central locking, alarm etc works perfectly now but still won't even turn around on the starter. Tried push starting it and using jumper cables but nope, not even a small hiccup from the engine.

 

[Carlv8415]

Checked the fuse to the starter motor ?

 

[Le Baguette]

Checked the fuse to the starter motor ?

I did.
As the car wouldn't start even when attempting a push start, I doubt the starter's the problem though?

As I somehow fried the 5 amp on the side of the dashboard I'm afraid I've somehow fried something else while swapping stereo head units..