Register Login
FIAT Auto Specialist Team
Reply
 
Thread Tools
Old 15-03-2011   #1
Join Date: Mar 2011
Posts: 1
Thanks: 0
Trader Rating: 0
USA 
Fuel level sending unit

What kind of electrical singnal does the fuel level sending unit send to the fuel gauge? (trying to figure out where the system is bad that is preventing the gauge needle from moving.) 1980 Pininfarina Spider, carb.
__________________
FIAT Forum Useful Links:
Donate to FF | Buy FF Merchandise | Classifieds | FF Insurance | How-to Guides

80spider is offline Reply With Quote Quote 
Old 15-03-2011   #2
Join Date: Jun 2007
Location: Bucks
Posts: 4,131
Thanks: 83
Trader Rating: 0
sludgeguts has donated!
United Kingdom 
Re: Fuel level sending unit

Quote Originally Posted by 80spider View Post
What kind of electrical singnal does the fuel level sending unit send to the fuel gauge? (trying to figure out where the system is bad that is preventing the gauge needle from moving.) 1980 Pininfarina Spider, carb.
They don't, at least ones i have played about with in the dim and distant past didn't.
The 'sender' is basically a variable resistor. power goes through the fuel guage and along the wire to the 'sender' in the tank. the amount of fuel in the tank governs where the contact on the variable resistor is, so with a full tank, the sliding contact will be at the lowest point on the resistor - therefore allowing highest current to pass to ground.
To test the fuel guage, turn ignition on and take the power lead off the 'sender' and ground it - no resistance should make the guage show full tank. If you suspect the 'sender' try cleaning up the grounding first.
the whole thihng is relatively simple... 12v to ignition sw, through fuel guage, through the 'sender' and to ground.
Thanks 80spider thanked for this post
__________________
Sick of the constant tax hikes?
See how much it costs you & write to your MP.
http://www.petrolprices.com/itsyourduty/

Last edited by sludgeguts; 15-03-2011 at 03:13.
sludgeguts is offline Reply With Quote Quote 
Reply
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump
Similar Threads
Thread Thread Starter Forum Replies Last Post
(T) Help With Level Transmition Unit vegeta3001 Fiorino (Mk1 / Mk2) 1 09-02-2011 12:08
(G) 1995 fiat ulysse - fuel sending unit May Ulysse 0 26-05-2010 13:11
(T) fuel level Duncan17 Cinquecento / Seicento 4 03-08-2009 16:43
(T) Hgt crank position sending unit adz182 Punto (Mk2/2b) 0 04-05-2009 18:14