Page 1 of 1

Position of Overdrive in line fuse

Posted: Thu Mar 05, 2020 7:04 pm
by JCS
I have recently had reason to replace the overdrive line fuse on my car. Whilst the workshop manual provides the details of the electrical circuit it gives no clue as to the actual location of the inline fuse.

Luckily I knew the fuse location as I had recently completed some rewiring. Others may not be aware of the fuse position, which is under the dashboard on the righthand side of the steering column (RHD Cars).

Re: Position of Overdrive in line fuse

Posted: Sun Oct 03, 2021 2:59 pm
by Norton
As I read your post decided to find OD fuse, LHD car.
The service manual gives a location. But I did not find mine in a spring clip, it was hidden behind the vertical part of shelf below dash. ( PO? ). I found it by following wires from control switch. The clip is still there, above brake fluid / handbrake warning light, but with current routing of wire it is out of reach.

Found a 15A fuse, service manual prescribes an 8A fuse. Didn’t have one, fitted a 3.15A and seems to work ok. Measured 1.1A of current for holding coil. Service manual says that operating coil draw 18-20A but it is momentary. If internal switch fails to open the 3.15 will blow. ( As an 8A also will ).
Rgds Harald.

Re: Position of Overdrive in line fuse

Posted: Sun Oct 03, 2021 4:56 pm
by Glyn Ruck
Warning ~ Fuse values


Remember that Lucas fuse values of 35 & 50 amp etc are old British 1 second blow standard.

Fuses you buy today unless you order specially are American Carry Current rating.

In modern fuse values you should select a fuse of approx half the value of the Lucas rating shown in Jaguar Manuals.

e.g. Lucas Horn fuse = 50 Amps. In modern US rated glass fuses you should fit 25 to 30 amp.

Failure to do this could cause a fire in our car's wiring in case of a short.

Re: Position of Overdrive in line fuse

Posted: Sun Oct 03, 2021 9:52 pm
by Norton
Thanks, didn’t know that.
Then it was timely to remove the modern 15A fuse and the modern 3,15 isn’t far from 1/2 old school 8A.
H