I keep blowing the 50A fuse right at the lead off the battery. I've got the factory wiring diagram that leads me to a big box labled Combination meter. WTF is a combination meter and is that prone to failing? I mean a 50A fuse to blow right on contact with power now is a pretty big short. Other then that the car was fine, and this starting happening with no warning at all. I want to get my car running again. Anyone got any ideas.

Thanks.

 

Is it right when you hook the battery up or when you turn on the ignition? Maybe try pulling all the fuses in the fuse block. I bet the wire after the main fuse has rubbed through the insulation and is grounding out somewhere.

 

No ignition is involved at all. Right when the battery power is ran to the car. There are no fuses blown in the car at all.

 

disconnect the negative cable and put a test light between the negative post on the battery and the battery cable... it should light up like a spot light (obviously you will need to have the positive cable connected)

then start pulling fuses until the test light goes out... then leave that fuse out and put the others back in and see if the test light comes back on... if it doesn't then at least you narrowed the short to that circuit

*edit* it could be your starter, or alternator or starter solenoid to

 

junk it

 

I've got every circuit disconnected right now and I'm narrow down to the COMBINATION METER. Like I said in the first post. WTF is a COMBINATION METER???

 

where is this box located and is the cover removable? if ur able to open it up u might see if there's any damage inside causing the problem.

 

that's the problem. I've disconnected the leads into the car. No problem. No fuses are blown in the car so there is no short up to that point either. The problem is between this combination meter and the fuse box. I dont' know what the combination meter is refering to. Is that the amp meter? That's the only thing I can think of, but not sure.

 

Combination meter is located in front of the nut behind the wheel.

just tow it to me. good timing also since I'm currently cleaning up the wiring harness in the blue RX-3 (I finished the 73 last Saturday).

 

Wacky you are nuts

isn't the combination meter on the gauge panel, did you add in any after market gauges or did you by chance use a newer style alternator

DAVE

 

okies

combination meter, so your rx3 is from 1974 to later (ie ap model)

basically the 50 amp fuse ya blowing is the main fuse for your electrical system.

it runs a white cable with red trace to the ignition switch and the alternator and the secondary fuse box..


the reason its called the combination meter fuse is cause the black box has a shunt under it and the 2 amp fuses (of memory) feed 2 smaller wires running away from the black box to ya amp meter to read the output of the alternator.


now with that explained..

first disconnect ya alternator regulator and see if the fault clears

if it has then reconnect the reg and disconnect the alternator B+ (large white wire with red trace)

as its my guess the alternator or reg has died. by doing that test it will show which one has died.

if the fault doesnt clear at all then start looking down the line to the ignition switch and secondary fuse box under the glove box

hope this helps

 

My car is a February 1973 production car. The 73 wiring diagram shows me a combination meter. I'll do the checks you said though SIM. Thanks for the help and I'll find out tommorrow how it works out. Oh and the car is 100 percent stock. Nothing has been added or altered.

 

hhhmmm interesting

pre polution rx3 usually had a 30amp amp meter and no shunt... unless american market ones were different!!

cool let me know how you go

 

sim will it hurt any thing if you change to a s4 s5 altanator?

 

hi mate,

you will need to upgrade the wiring for the B+

and change the wiring to suit the internal reg of a series 4 alternator.

series 5 alternator has different connections to the series 4 as well..

 

Ended up being the alternator. Now trying to decide if I'm going to upgrade or just leave it stock for now. Figure I might as well change the regulator if the alternator went out.

 

Nah, no need to upgrade...Let the new owner deal with it.

 

Ha Ha. Funny guy. I want to get the car back on the road for the Meet Friday night.

 

you can always tow it to the meet

 

bingo!! haha

if the car is stock leave it stock

yes its a good idea to replacve the reg when you replace the alt.

i can get the rx3 reg for $50AUS here brand new. but im sure you could get them cheaper over there.

make sure its an rx3 one as the wiring is different from rx2 and rx4 external regs..

cheers