mwaedow

I'm currently having an issue with my 96 Civic. I recently swapped in a B16a2 from a 2000 Civic Si, complete with dash, cabin harness, everything to convert to obd2b. It runs fine, no CEL or anything, as long as the C131 connector (green) next to the ECU is NOT plugged in. When I plug in the connector and turn the key on, the CEL flashes for a brief second, then goes out, along with the charging system indicator light. Fuse #15 (Alternator, Speed sensor) blows instantly, and I'm wondering why. Do I have a bad ground, a short circuit, or something else? Any help would be appreciated.

mwaedow

bump

Matt93eg

Not to seem rude or anything but why bump your thread only 6 mins after posting it??

Make sure you don't have any exposed wires or anything going to the alternator that could be bare and ground causing a short.

mwaedow

sorry, I'm just impatient. I checked the wiring to the alternator, and it's all fine. As long as I don't plug in the c131 connector, the alternator works, and charges the battery, so I think the problem must be in something else related to that connector. I unplugged the VSS and tried again, fuse blew again, so I don't know what to look for.

dumpsterbaby

check your o2 wiring especially your secondary o2 that runs after the cat, i had the exact same problem and turns out the secondary o2 wiring was exsposed and touching the chassis blowing the alt/vss fuse

mwaedow

thanks dumpsterbaby, I'll check that out, I've had to modify the second O2 wiring for the swap already, so maybe I messed something up.

mwaedow

ok, I checked the wiring on both O2 sensors, everything is intact. I unplugged the sensors, just to remove them from the equation for a second, and again, popped the alternator fuse instantly. Does anybody else have any ideas? this C131 connector has 10 wires. 5 are PGM-FI, 2 are for the back-up lights, 1 is for VSS, 1 is for the fans, and 1 is ground. I can't figure this thing out.

mwaedow

bump

dumpsterbaby

ok well most likely u have an expsosed wire somewhere grounding out, easiest way to find is to do what u just did an start unplugging things to eliminate them, in terms of the engine harness i think the bare minimum u need to have connected is the crank position sensor, dist, and fuel inj, for the engine to start, i would start disconnecting things one by one then start the engine an see if the fuse pops, i would take a good look at the wiring than runs for the vss and the wiring that runs underneath the intake to the alt

mwaedow

I'm just baffled that the vehicle runs as well as it does with the connector unplugged, considering that 5 of the wires are for PGM-FI. You would think that leaving it unplugged would cause major driveability problems, but there are none. It performs normally, but the cooling fan doesn't turn on, my speedo is dead, and I have no reverse lights. other than that, there are no apparent problems. Is it possible that the ground wire on the plug itself is faulty? What if I spliced in a wire and grounded the connector directly to the chassis?

nitewolf

check your engine harness make sure everything is plugged in right and make sure there's no bare wires. most of the time its the wires on the intake manifold support/bracket that tends to rub exposing wires. check grounds. replace with same recommended fuse. i did all of this including my deck harness replaced my alternator to find out it was my fuel pump.

gl with the fix.

mwaedow

I discovered that on the B16, the intake manifold bracket is in no danger of rubbing the wires that run under the manifold. All of the wires are intact and for the most part, sheathed with conduit. I checked every wire under the hood, and there are no wires or grounds that are suspect. I did find a wire running to the under-dash fuse block that had been cut, and after reconnecting it, my instrument lights work! Hooray. I purchased the dash harness from a junkyard, came from a car that had an alarm equipped. I don't use an alarm, so there could be other mods to that harness, causing my issue. My question is: does anybody know the common modifications that need to be made for a wire harness to facilitate the use of an alarm system? (which circuits are commonly tapped into) I just want to revert it back to stock.

mwaedow

Found the short, it was some wires on the dash harness that were touching each other. Fixed it, problem solved.

mrharmonic

sounds like short but bump bro