My speedo, fuel, and temp gauges all do not work, was wondering if anyone could tell me where all the grounds are for these gauges and what the most common problem would be for these gauges not to work. I have all the tools to ohm the gauges and sending unit if need be, but im hoping the grounds are what are causing all my troubles i just dont know where the grounds are. I can tell you this there are 4 black wires by the silonoid not hooked up to anything, 3 with rubber plugs that looks to go on a threaded screw or terminal and 1 circular one that looks like it would be screwed into the tube some where.
The gauges all ground to the metal case which holds the speedo cluster. the case grounds to the dash, the dash to the tub, tub to the frame, etc. My ground was bad because the new paint on the dash stopped the current from passing. check the resistance between a bare metal spot on the dash and the metal ring of the speedo. there should be little to no resistance. If that is the case, the grounding should be ok. Search for threads on this subject, there are thousands, and some good diagrams to follow for checking voltage at the various posts.
The speedo works on a cable and the other two gauges get power through a mechanical regulator built into the fuel gauge. When this regulator pops, no power to either gauge or if it's points stick, too much power which lets the magic smoke out and the stop working.
86/00 CJ7 Laredo, 33x9.5 BFG AT's, 'glass nose to tail in '00, 'New' frame,wires and plumbing in '09. Carter BBD Carbed 4.0 HO in '10.
89 YJ Renegade. BBD Carbed 4.0 HO. Locked front and rear with 33x9.5 BFG AT's
Some Canadian Bush Jeep Runs and Build Photos: http://mikeromainjeeptrips.shutterfly.com (10 new albums added Sept 16/10)
I ran a seperate ground wire all around my jeep, just to eliminate
bad body grounds. I take it your jeep is all together. It will be a pain to
do, but it will save you alot of headaches. I did mine as I was putting it together.
1978 CJ7, Driving, but never finished