16vsilverstreak

Hello. I just finished running, soldering, and heat shrinking wires for the Continental (VDO) TR7412UB-OR radio in my ‘85. After running tests and before clicking it in place I remembered a VW radio wiring trick. On at least the MK1 chassis cars there was a brown with red tracer wire off of the ignition that powered the seat belt warning system. It was activated when the key was inserted. No turning of the key required. Before I dig into the schematics does anyone know if there is a similar circuit off of 928 ignition switch? Thank you.

Alan

Yes there is a "key in" switch - but why do you want that? - there is also an "accessory like" connection (R) specifically for the radio, as well as constant power (30).

What are you trying to achieve?

Alan

16vsilverstreak

I’m trying to achieve power to the radio when the key is inserted into the ignition switch. Thank you.

Alan

The issues with the key in switch are its not easily accessible and it is a very small low power switch - designed for signal purposes only (Key Based Warnings: key left in + door open, key out + marker lights on, key out + parking lights on etc).

I think you'd need a relay here to reliably support the power required for a head unit. It does go to the chime relay - so its in the right approx area. I'd still say the (R) is better - it disables during starting - the key in switch does not.

Alan

16vsilverstreak

Alan,
Than you for the information. I would definitely install a relay if I use the signal wire. Thanks.

Bigfoot928

Key in switch would be nice for NAV boot up and backup camera....