lite1979

Before anybody asks, yes, I read the TSB, and no, Fuse 15 is not blown, but I still feel that has something to do with it. The VSS is new, as is the O2 sensor. Connections to both the VSS and the front O2 look good with little/no corrosion. I've sprayed both with contact cleaner as well just to be safe.

Of all the fuses in that inside block, Fuse 15 pulls out the easiest. It almost falls out. I thought I had some dielectric grease here to see if that would help complete the circuit, but I can't find the stuff, so I may buy some more tomorrow.

Has anyone had to replace his fuse block to fix this issue? If it's just the one slot that's bad in the fuse block, can it be repaired? How hard is it to remove the block?

I'll be jacking the car up and checking the wires under the intake manifold tomorrow, and I'll post my findings here. I have a generic OBDII scanner as part of the VCDS software I use for my VW/Audi work, and I have a good multimeter if that'll help at all. Any input appreciated.

Doing this for my new roommate, who needs to pass a New York State Inspection here in Buffalo.

Cheers,

Lite

Former User

With fuse 15 installed, turn the key from off to ON(II). Does the charging system light in the cluster (battery symbol) turn on and stay on?

Do both top test tabs of installed fuse 15 read battery voltage to body ground?

lite1979

Yes it does.

Yes to this as well. I only got 11.00 volts at each tab, so I checked the battery voltage, and only got 11.11 volts there. The car sat for quite a while at the previous owner's residence.

This leads me to suspect a broken wire/wires (as opposed to a grounded one, which would be what normally blows fuse 15, right?). Should my next step be to jack the car up and inspect the wires under the intake manifold? Times like now I wish I had a heated garage.

Thanks for the reply!

Former User

That's a possibility.

The next step is to test whether the VSS and O2 sensor plugs get battery voltage.

lite1979

Ok. So with the key in the II position, do I check for voltage from each pin to ground in the VSS and O2 plugs, or am I looking for voltage across pairs of pins? The heated circuit for the O2 should be pretty straightforward, but I'm not familiar with the function of the three pins for the VSS. Thanks again.

Former User

The Blk/Yel wire in the O2 sensor and VSS connectors(wire harness side) supplies voltage. Start by using the engine as ground for the measurement. Key is in ON(II).

lite1979

No voltage at all in the O2 sensor, and only the blue/white had any voltage (4.56V) on the VSS. The black/yellow (middle, iirc) and the black yielded 0 volts on the VSS.

Former User

One or more Blk/Yel wires are probably broken around connector C115. It's time to check behind the IM for broken wires at C115. See fuse 15 TSB.

lite1979

Thanks. Should I approach it from underneath the car? I'm afraid I don't have a lift, and with no heat or garage door where the car sits right now, if I can approach it from the top side of the engine bay, it would be much more comfortable. I'm prepared to bundle up and work from the floor, though. I've done it for my own cars before.

Former User

Access is best from below the car. The area of interest is just above the oil filter.

lite1979

Getting the intake manifold bracket off was harder than I expected. The two lower bolts weren't too bad, but the one holding the top of the bracket seemed impossible from underneath. When I got on top of the motor, though, I realized I could get at it from above and it came out easier than the other two. Once I got it loose, I could see that multiple (at least two) wires had lost their insulation by rubbing on the bracket. I'll spray down the area with brake kleen when I get back to it (the entire area is covered in oil; valve cover gasket failure?) and check the wires one by one to see which need tape/replacement.

Former User

Looks like you found the problem.

lite1979

So I finally got around to fixing the wires, but I can't manage to find the two things that plug into this connection. It seemed to sort of "pop" off when I tried to move it, but not being too familiar with these cars, I can't see any plugs behind the harness connections, and they seem to be plugged. The TSB shows them both being connected to another part of the harness, but I don't see or feel anything up there, and I've looked from every angle without taking off the intake manifold. Is this normal?

Based on this pic




I thought it might be normal for me not to have anything to plug into, but as soon as I started the car, I got codes for the heated circuit and of all things the knock sensor (maybe I messed it up while having my hands in the area? I'll check tomorrow). The speedometer doesn't work, either. Boo!

grumblemarc

iTrader: (4)

Dead end plug. Leave it alone.

lite1979

Thanks. I didn't touch them.

lite1979

So I have the next two days off, and I'd like to get this car's VSS and heated O2 circuit fixed. Other than taking the IM support off and looking at those wires again, are there any other common points of failure for the black/yellow wires that supply voltage to the VSS and heated O2 circuits?

I got a code for a broken circuit for the knock sensor. Is it possible this is related to the lack of a speedo and bad heated O2 circuit? Maybe the same wire powers all three?

I can't wait to get this car on the road so my roommate doesn't have to take a taxi everywhere...

94EG8

No, not really.

The knock sensor is unrelated. It only uses a single signal wire that runs to the ECU. It doesn't have a power wire or a separate ground. Normally when you're getting a knock sensor code then sensor is actually bad, half the time they will quite literally be broken in half.

lite1979

Ok, so while removing the IM bracket a second time around, I figured I'd see what was up with wire along the strut brace. It has a red wire running from a fuse near the battery all the way to splice into the black/yellow wire going into the harness at the alternator.

That black/yellow wire that would normally go to the alternator is cut at the harness. Is this wire related to the one that I just repaired under the IM? I'd hate to remove all the tape and stuff if the alt. needs to be connected to that wire to complete the circuit...

If my previous wire repair went well, should I just be able to re-connect the black/yellow wire going from the alt back to the cut black/yellow wire coming from the harness?

lite1979

It's based on these two pics that I believe the bypassed black/yellow to the ELD on the alternator is my problem. Please chime in if I'm wrong: