Rover 400 Rear Screen Heater - JohnS
I have a 1998 Rover 400. The rear screen heater only works occasionally - click the switch and it may come on after several minutes (or hours), it may not (usually not). I think the switch and relay are okay. Is there an electronic device that sits between the switch and relay that determines when to automatically switch the thing off (after 15mins, I think)? If so, where is it and how can I test it? Any ideas?

Cheers,
John.
Rover 400 Rear Screen Heater - Billy Whizz
sorry, I have looked through my mate's R400 workshop manual, all 1077 pages, but there is no mention of the rear window demister timer (demister sometimes known as the backlight heater).

But no wiring diagram in manual, I believe these are located in a separate Electrical systems troubleshooting guide (or some such, that he doesn't have tho'.)

Doesn't it say anything about whether there is a timer or not in the owners guide?

Billy.
Rover 400 Rear Screen Heater - Billy Whizz
Forgot to say it is the 1996 model (rounded shape). Same as yours, tho'?
Billy
Rover 400 Rear Screen Heater - Toad, of Toad Hall.
Its the MFU. (Multi Function Unit)

Lights on buzzer and interior light timing may also be wrong.
--
These are my own opinions, and not necessarily those of all Toads.
Rover 400 Rear Screen Heater - JohnS
Yep, it says that the heater will cut out automatically after 15 minutes.
As you say, there's no reference to it in the manual. If you look in the manual for the previous model, however, (God bless Halfords!) it gets a mention in there. As Toad of Toad Hall says in his reply, its probably the Multi-function unit, located by the fuse-box below the steering columm, I believe.
Cheers, John.
Rover 400 Rear Screen Heater - Toad, of Toad Hall.
As Toad of Toad Hall says in his reply, its probably
the Multi-function unit, located by the fuse-box below the steering columm,
I believe.


And hemmed in by a million wires.

Of the two rovers I've owned and the one other I have regular contact with all have had MFU issues.

I didn't dare touch mine in the old one and a scrap one will be no use because they all go wrong.

Can't really propose a viable solution - perhaps hardwiring and living without the pointless timer?
--
These are my own opinions, and not necessarily those of all Toads.