C70 radio issue
 

My step daughter recently bought a Y reg C70[it's a 2.4 lpt manual if that makes a difference]when we picked it up the seller said a previous owner had fitted LED bulbs in the rear light units.Step daughter now reports that when she applies the foot brakes the radio cuts out and comes back on when the pedal is released.Could this be down to the LED bulbs or are we looking at deeper issues?

take out led bulbs and see if it makes any change to raidio problem might be a cheap easy fix . check all earth connections

I do not know the answer and, not having considered a Y C70's wiring diagram but, I assume that the footbrake circuit/lights are potentially 'live' all the time even when the iginition if off. It just takes a push on the brake pedal to make the circuit to activate the brake pedal switch and stop lights. At least that's the way it works on my '98 V70.

The brake pedal switch is a complicated little 'gem' (requiring set up) being off when when the switch button is not touching the pedal when the brake pedal is not operated.

When the brake pedal is operated the pedal arm moves down making contact with the switch button so making the brake light circuit.

I would be looking at a common earth connection between the head unit and the stop lights for the fault.

Bob :)

Does the radio actually cut out - i.e. power off - or just lose reception? If the latter then yes it is likely the bulbs. The C70 FM aerial and amplifier is at the rear and the MW aerial is behind the rear bumper.

I'm basing that as I've seen LED drivers and 5v adaptor affect DAB and FM reception on cars.

As we're on a day out[to Elvington] tomorrow I'll ask her that question Tannaton.One other thing I forgot to mention is it has a tow bar fitted but a previous owner has removed the tow ball and electric socket[s]so I suppose it might also depend on what they did with the wiring when they removed those bits.

Regarding the towbar: it is more than likely the ball and electrics were never fitted. It is a popular handling mod on the convertible to fit the towbar without the ball to 'improve' handling.

As Tannaton mentioned there is an additional antenna within the rear bumper on the drivers side. Remove the boot trim panel and you should find a blue box connected to a coaxial cable and a small black wire going through the body towards the bumper - next to the light cluster. On the attachment you can see the large round hole below the light cluster. On the passenger side the cable for the reversing sensors goes through there and the corresponding hole on the drivers side is for the antenna cable. This is in addition to the electric aerial on the rear wing.

Apparently when she applies the footbrake the radio goes from playing normally to giving out "static" and as soon as she releases the pedal normal service is resumed until of course the next time she applies the brakes.

In that case as simmy suggests above, replace with normal bulbs and if that cures it then that's the problem - quick, easy and cheap. Having confirmed the diagnosis, you can always try some different types of LED bulbs if your (her?) heart is set on them.