denviks Posted December 20, 2007 Share Posted December 20, 2007 hi all...let me just start by saying merry xmas :D i have a problem that developed tonight on my disco. she is a 3.9 v8 efi on a L plate ( 300 shape.) she is fitted with the 4 speed auto box. anyway here is what happened. i headed into town to pick the misses up from work. i sat outside her work for 30 mins with the engine turned off. i started it up and headed up the road. 2 mins in and the reg cog light with a thermometer flashed up and went out.... then came on permenatly...... i drove very carefully to local garage when i got some auto fluid....i checked the level and to be fair it seemed fine.....nice red looking fuid that smelt good.... i drove the truck the rest of the way home and it felt fine. nice smooth gear changes..... i was very gentle with it. after getting it home i checked the front cooler that runs in front of the rad and that seems clean.....i left the truck tto cool down for 2 hours. i went out and put the key in the ignition and turned it on without starting the truck.... the light comes straight on i am thinking along the lines of an electrical fault? am i correct? can anyone point me in the right direction of things to check....and their location........tis my first v8 cheers in advance guys Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted December 20, 2007 Share Posted December 20, 2007 On the "bog brush" oil coolers the temperature switch is on the passenger side I think, it's either duff or the wiring's wonky/damaged. You'll need to remove the grille and then get a big spanner onto it - careful what you lever against when undoing it, you don't want to damage the cooler. Quote Link to comment Share on other sites More sharing options...
denviks Posted December 20, 2007 Author Share Posted December 20, 2007 On the "bog brush" oil coolers the temperature switch is on the passenger side I think, it's either duff or the wiring's wonky/damaged. You'll need to remove the grille and then get a big spanner onto it - careful what you lever against when undoing it, you don't want to damage the cooler. thanks mate....gonna get changed in a min and head out there and have a nose.....see what i can find.......will report back Quote Link to comment Share on other sites More sharing options...
denviks Posted December 20, 2007 Author Share Posted December 20, 2007 thanks mate....gonna get changed in a min and head out there and have a nose.....see what i can find.......will report back ok here goes with the findings.. i went straight to where you said bud and found the electrical connector.... well described... so first things first... i checked the gearbox oil level....i dipped it 3 times and got 3 slightly different readings but all within the levels....all nice clean sweet smelling oil.. so i had a look at the connector and found that it was pretty clean ..... ( can i run an electrical check on this to make sure its right?) so i turned the vehicle ignition on with the connector on the sensor......the warning light is on.......if i pull the connector off the light goes out ... so would i be correct is saying its the sensor at fault?...after all the engine and gearbox are cold and have not been moved for over 12 hours now.... is there a test i can run on the sensor? as i say above the truck drives well .....was just a bit worried to see an extra red light on the dash.....if i leave it disconnected now do you think i will be safe enough driving it around until i get a new sensor?? any advice very welcome Quote Link to comment Share on other sites More sharing options...
wrcwrc Posted December 20, 2007 Share Posted December 20, 2007 you checking the auto box level on the dipstick whilst the car is running yeah??? if you arent it will read higher than the true level... Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted December 21, 2007 Share Posted December 21, 2007 Cold, idling in neutral is the correct way to check it IIRC. Yes you can do an electrical test on the sensor - you've just done it by unplugging the wire if the light had stayed on I would suspect wiring (or a sensor that defaults to closed-contacts). Anyway, I think we can safely say the sensor is dead. Part number is: prc3139 to April 1990 / prc8473 onwards Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.