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jsrieck
11-01-2015, 06:52 AM
Hello! I've got a RHD S3 109 FFR. I'd like to sort out the gremlins in the instrument panel. I have the green bible as well as the military operation manual.

Could y'all please help me understand how to troubleshoot the problems (overview below)? Do I need a multimeter? Any other specialized tools?

Thanks!

Here is a summary of what works/doesn't work:

Left Side
Left turn indicator (orange) - the right side lamp (green) comes on when the left turn signal flashes...
Speedometer - works!
Odometer - works!
Tripometer - the reset thingy doesn't reset, it just twists the numbers up
Oil pressure indicator (green) - don't know
High beam indicator (purple) - works!
Cold start indicator (orange) - always on...

Right Side
Right turn signal indicator (green) - works, but for the left flasher. Turn signal stalk is stiff and won't click for the right signal....
Water temp - pegged at the bottom, something not right
Oil temp - seems to work, moves to the little tick mark just under 85C, who knows if the gauge matches reality...
Fuel gauge - doesn't work for the right tank, but does work for the left tank...assume its a sender?

mearstrae
11-01-2015, 02:45 PM
A multi-meter and test light are invaluable in trouble shooting electrics. You have to know if the voltage is getting to something, or leaving something, before you can know if it works. Checking Ohms with the power off lets you know if a wire is broken or shorted out against something, or if something is wrong inside a gauge. You don't need top of the line test gear for these simple electrics. Always start at the source of power and work outwards, so you don't drive yourself nuts.

'99 Disco II
'95 R.R.C. Lwb (gone...)
'76 Series III Hybrid 109
'70 Rover 3500S

LaneRover
11-01-2015, 06:45 PM
Also, check your grounds - what you describe with the turn signals sounds exactly what used to happen to mine when the grounds were iffy.

lumpydog
11-01-2015, 09:57 PM
Oil pressure indicator (green) - don't know


When you click the ignition key one position to the right, this light should come on and stay on until the engine cranks and builds oil pressure -then it will turn off. If it never lights up as described, check the bulb, check the wiring, check the switch (will be mounted to the oil canister/filter mount).



Cold start indicator (orange) - always on...


This one has potentially two switches to make it light up. First, the choke cable has a switch that is mounted to the cable. A spring loaded "bump" on the switch pops into a hole made available when the cable is pulled out - that turns on the light. You may also have an "Otter switch" that is in line with the ground of the choke switch. The otter switch is thermal based and is mounted to the engine - it grounds out the cold start light circuit when the engine is warmed up and this then lights up the cold start light if the choke cable it pulled out.

If your truck has the otter switch, a simple way to test if it's faulty would be to see if the cold start light is coming on right away, before the engine is even warmed up. Pull out the choke, and turn the start key to the point where the dash lights come on - but don't start it... and see if the cold start light comes on. If it does, that would point to the otter switch because it's grounding the circuit without the engine being warm.

But, even if it's a faulty otter switch, the the switch on the choke cable should be able to break the circuit if it's functioning properly... and kill the light when pushed in.

If you have no otter switch, check the switch mounted to the choke cable - i believe it is mounted to the cable in the engine bay (vs behind the instrument panel) on a series 3

kenscs
11-02-2015, 06:52 AM
Right Side

Turn signal stalk is stiff and won't click for the right signal....

I had this problem. If you have the Tex Magna-Lite signal assembly, I fixed it two ways. One, I took apart the unit and found that the long Machine Screw that goes through the center of the turn stalk had fallen out, so it was not getting proper leverage and kind of just "worming" around inside the unit. I replaced that screw (you will need to find a source for BSF threaded long screws, don't strip the unit by trying to fit in hardware store UNF or Metric Screws) and it worked great from a Turn Lever aspect. While I had it apart though, I ordered a new Rubber Wheel for it from Pangolin 4x4 (the only source I know of) and now it works as well as my 2016 cars turn signal.

Not sure if the S3 had the magna lite. I think they only used them until 1972. In any case, I would just take the whole signal apart, and see if you can figure out if a screw rattled loose after all these years. Easy fix.

On the multimeter question, Absolutely you will need one of these. As mearstre states, a necessity and does not have to be fancy. I keep a bunch of the Harbor Freight $5 ones around if I am doing basic first-pass trouble shooting just in case I hit a high amperage spot and blow the meter. When I narrow down the issue and am testing for milliamp drains, etc, I switch to a good one. I have to say, in all the years of "double checking the voltage or amperage" with the "Good" meter, I have ever found a difference between the $5 Harbor Freight one and the $50 Auto-oriented one. It is more a difference of durability than accuracy IMO.

You should consider getting a slight better one designed for automobiles so you can check things like dwell angle and RPM when you tune the engine up. Amazon has a bunch of modestly priced ones that work great. And realistically, all the meters have fuses inside them that will blow if you screw up the connection and blast it with too much voltage or amperage. I just feel better using the $5 one first.