Doug, I had to do a little re-organizing of my web space, I moved the diagrams to here:

http://web.njit.edu/~jjj8778/Civic/

There's two folders there, one for 1200's, one for CVCC's.

It looks like that fuse doesn't have too much on it. I'd unplug the carb solenoid, replace the regulator (I've seen some pretty cheap on e-bay, but a good used one will do), and if you can, reach up under the dash and unplug the gauge connectors. Turn the ignition on, see if the fuse blows. If it does, don't rule out a bad ignition switch, and the alternator is in the same circuit too, but I don't know if it can cause the fuse to blow. Maybe.

If the fuse doesn't blow, it's something you disconnected. Plug stuff in one by one to see when the fuse does go. You might want to use an ohmmeter to check resistances before you plug stuff in, you might find a direct short to ground. Other than that, there may be a place where the wire rubbed the insulation off after 30 years, causing a short there.

By Doug Bergerson (Matcho) (12.219.189.139) on Thursday, December 02, 2004 - 10:58 pm:

Has anyone had the same problem with a 74 civic? The 10 amp "regulator" fuse blowing as soon as the ignition is turned on?

I have isolated the issue to the black wire with yellow stripe.

However, I could not access the diagram posted at:

http://web.njit.edu/~jjj8778/civic/wiring/

Page could not be displayed.
I DO have a haynes manual with wiring diagrams though.

I don't have all of the items listed above though.

My fuel pump is mechanical, not electric

I have two thermo switches/sensors. One of them is at thebottom of the radiator, the other is (used to be) on the back of the intake manifold(I replaced it with a sender for a temp gauge I bought.

I don;t think I have a speed sensor

I have disconnected and sealed the oil presure wire and the wire that ised to go to the temp sensor on the intake, so both of those switches are out of the picture. However, that does not mean that the wire to either one (temp or oil) is not shorting out somewhere, just mean I disconnected them and taped the wires.

Come to think of it, the temp gauge in the dash never worked, so thats a hint, huh?

Where is the cooling fan relay on a 74? I don;t see one, but where do i look?

I'm ready to run new wires and bypass the old ones. I bought a fuse block for 6 blade type fuses for just such a fix.

Any help would be appreciated

Doug Bergerson
dmbergerson@mchsi.com

By Kabuto (Kabuto) (68.116.85.75) on Monday, September 22, 2003 - 08:10 pm:

Thermosensor "A", standing on the passenger side looking at the engine, follow the upper radiator hose to the housing that bolts to the head. Just to the right of the housing and down there is a heater hose that connects to the head, just in front of the hose is the sensor. The wires come out of the engine harness that the starter is on as it passes under the radiator hoses and such. Originally they had a black rubber conical cap over the sensor and the two wires came out of the cap at the top, the cap might be there hiding the brass sensor under it. Unplugging the sensor will take it off the circuit and not disable the car so if the problem goes away... Thats it! Good Luck!

By Aron (64.91.160.226) on Monday, September 22, 2003 - 09:11 am:

ok, it runs for a minute or two, then the regulator fuse blows. I am trying to check the other stuff on this circuit, but I still can't find "thermosensor A." Can anyone give me more help? can I follow a wire from somewhere to it? any other suggestions??? Thanks!

By Aron (64.91.161.133) on Saturday, September 13, 2003 - 08:26 pm:

Oh yeah, I used the wiring diagrams thoughtfully posted here:
http://web.njit.edu/~jjj8778/civic/wiring/

By Kabuto (Kabuto) (68.116.85.75) on Saturday, September 13, 2003 - 06:29 pm:

unplug each item on the circuit, one at a time and check to see if the fuse blows. It is easier to have a circuit breaker in place of the fuse so that you don't have to replace so many fuses. I have found Thermosensor "A" to be a problem a few times, it will blow the fuse as the car warms up and can be a real pain to find. The thermosensor is located at the rear of the cylinder head just below and forward of the distributor housing. By rear I mean the passenger side end of the head. Idle cut , and pri/sec solenoid are on the carburetor, you can disable them all by diconnecting the wires to the carb at the firewall right behind the carb. good luck.

By Aron (165.121.139.153) on Saturday, September 13, 2003 - 03:40 pm:

1978 CVCC: When I turn the key, the "REGULATOR" fuse immediately blows. I replaced the regulator. No change. I unplugged the fuel pump. No change. The curcuit associated with the regulator fuse is a black wire with a yellow stripe. It covers:
regulator
primary/secondary main cut-off solenoid valve
thermosensor A
idle cut-off solenoid valve
fuel pump
speed sensor
oil pressure light
cooling fan relay

what should i do next? i don't even know where to find this stuff! Thanks,
Aron