Antenna/Aerial Relay

[Casey]

Just in case in helps anyone in the future, this "Power Antenna Relay" (p/n FA 0167 740) is situated near the CPU unit, near your right knee when driving.

I was looking around that area for the source of an annoying "buzzing" sound (could be a chattering relay) and this is the next item I need to eliminate as the source. I've confirmed the sound is not coming from the CPU or the "Relay Check Lamp" module (which has a reed relay inside).

I will be disconnecting this relay next, but it's a faff to remove the connector and I ran out of time. Job for later

Antenna Relay.jpg (91.36 KiB) Viewed 27830 times

Antenna Realy Circuit.JPG (147.2 KiB) Viewed 27830 times

[Casey]

Wow, I forgot to post the result of disconnecting the Antenna Relay.

Just for the record, it hasn't solved the irritating buzzing sound I get for up to the first 40 miles of driving (but usually for only a few miles until around the time the choke magnet releases).

Depending on which wiring diagram applies to UK Series 3 cars, there may be a "Coolant Level Unit" situated in the same area as the source of the buzzing (I have to say I haven't spotted it - yet at least). Looking at one of the (many) wiring diagrams, the unit does have an oscillator circuit inside (see below), so might be the source of the buzzing I'm hearing. I haven't worked out exactly how it functions, but note it does have a connection to the "Choke & Check Relay" and its associated oscillator. As the buzzing sound I get is closely connected to the choke operating period, this might be it! I'll look into this when I have time and report back.

The buzzing is quite low level, so I've lived with it for ages (having checked many prossible sources already) but I would like to get it sorted at some point!

Coolant Level Unit.jpg (91.75 KiB) Viewed 5791 times

Coolant Level Unit, extract from Wiring Diagram.jpg (37.44 KiB) Viewed 5791 times