Former User

What do the other two plugs go to? Can you post a picture showing the number of pins and how they are arranged in the green plug?

Is it C131?

RPMvulocity

i jus grabbed this picture from ebay, this is from a 99-00 civic that has only two plugs(for example purpose) and that green plug from the engine. the 96-98 has 3 plugs and that green plug that is part of the engine harness. the big plugs goes into the ecu and the the green plug goes in a harness that comes by the glovebox

Former User

Does your green plug match C131 with respect to pin pattern and wire colors?

RPMvulocity

yup that's the right one, im jus making sure it's all correct

RPMvulocity

There is continuity from the fuse to the main relay and ecu

RPMvulocity

Do u know how much resistance there should be before the fuse and after? I wanna measuer resistance from each component before and after the fuse but I don't have a spec for it.

Former User

It hard to know how to interpret this result without some details about how you did the test. What wire(s) was probed? What was disconnected? etc.

RPMvulocity

I checked continuity of the blue/white wire. I did it with my dvom on diode mode...all it does is sends a signals through the wire that you're checking continuity and if it reaches to the other end where other probe is the dvom will beep, but if there's a short or open somewhere it wouldn't beep. it's the resistance I don't know the spec

Former User

You know that there is a short in the circuit. You now need to pinpoint it. However, I am not sure how the diode mode tests for a short. What all was disconnected for the test?

Here's the conventional method to test for a short:

Set the multimeter to measure regular resistance or continuity. If you measure continuity to body ground, then there is a short in the Blu/Wht wire or in the dash fuse box. The next step is to unplug the dash fuse box connector for the Blu/Wht wire and repeat the test. If there is still continuity to body ground, then the short is in the wire not the fuse box.

RPMvulocity

Okay, did exactly what u said is it's getting continuity to ground with everything unplugged at the main relay plug...so that means the blue/white is the cause of the short somewhere...does this wire come directly from the fuse? Or does it route to other things then to the main relay and ecu?

Former User

Your test result verifies that you have a short and that it is in the Blu/Wht wire, assuming that you unplugged the (1) main relay, (2) ECU connector C, and (3) the dash fuse box connector (C420) that carries the Blu/Wht wire. All were disconnected, right?

RPMvulocity

Correct, so would the starter still be able to crank the engine even with a short in the blue/white wire?

Former User

Yes. A blown fuse 31 should not prevent the starter from cranking the engine.

Former User

Your options for fixing the short are either to try to locate the damaged spot of the Blu/Wht wire and repair it or to run new wires from C420 to the main relay and ECU plugs. Note also that it's possible that the short is in C420 or the main relay or ECU plug.

RPMvulocity

o the main relay and ecu, do I jus cut that blue/white wire entirely? Might explain how I exactly can do this. Is there a way to determine if the short is in the c420 plug, ecu plug or main relay?

Former User

Guess what. There's some more short tests to do before you cut and splice any wires. It turns out that the Blu/Wht wire passes through connector C131 (terminal 22) (see post 26) on its way to the ECU. I think you said it looked damaged, right? Maybe that's where the short is. Unplug the connector and inspect the Blu/Wht wire terminals and wires for damage. Then, with all connectors unplugged including C131, redo the short tests at both ECU and main relay plugs, as well as on both sides of C131.

RPMvulocity

Jus redid the short test and include that one u jus added and still the same result of having continuity to body ground, I inspect that wire and it seems to be fine from what is visible then tucks away into the dash

DCFIVER

Sure was a lot of testing you did there. First thing i would have done is to look at the amperage draw and the voltage drop of the starter...

RPMvulocity

I wired how you said earlier from the c420 plug straight to the the ecu and main relay...still blowing the fuse

Former User

I would expect that only one of the two sides of C131 (dash fuse box versus ECU side) has continuity to ground. Is this what you found? If so, which side?

Former User

I assume you bypassed C131 for the rewiring. Is this correct?

The fact that the new wire did not repair the short suggests that it is in or near one of the connectors (C420, ECU, main relay). If you did not bypass C131, then it is also a candidate. Results from your earlier C131 test may allow you to rule out the ECU side of C131 and the ECU connector.

If you now cut the Blu/Wht wire near each unplugged connector, you can test the cut wire for continuity to ground to determine whether the connector itself has the short.

Former User

Not sure how this test would have helped to pinpoint the short.

DCFIVER

The title stated that the starter keeps blowing a fuse. This is not necessarily the result of a "short". An excessive amperage draw is a likely culprit and I would have simply eliminated that first...

RPMvulocity

To measure amp, wouldn't I need a inductor deal for a dvom? Aight, let's get that out of the way. How do I do it and what's the spec?

Former User

Excessive amperage draw is just a fancy name for a short. If you are familiar with the circuit being discussed, fuse 31 protects the starter signal circuit not the starter, so a faulty starter would not cause this fuse to blow.