help!fuse 10 keeps blowing and i have no guages!

[ak96ss]

The only things that should be running directly off of fuse 10 are:

Back Up Light Switch
Instrument Cluster:

Check Engine Indicator
Connector C1 Pin 23
Connector C2 Pin 6
Connector C6 Pin 3

Active Check Control
Seatbelt Warning Timer

All are green/white wires, .5mm in size. Page 0670-7 of the ETM.

EDIT: Unloader relays K7 and K5 are pulling power for their coil through fuse 10, as well as the coil for the starter solenoid, but that's why you should pull them out first and see if the problem still occurs. If you pull the unloader relays and the problem goes away, you can eliminate all the items listed above and concentrate on where the short is. Mea culpa, I've fixed the above.

[Stevie30]

Questions

Does the fuse blow when the switch is turned on, or when starter is engaged? Does the car start and run? When did this problem begin? Maybe we can get this problem solved.

[Julien]

i had this when my reverse wire got loose and grounded itself out. It runs from your tranny to inside the cabin via the shift boot (rubber)

[Dibo718]

Fuse 10 keeps blowing on me also except 1. my reverse switch isnt connected and hasnt been for months now without any problem and 2. my seat belt light connectors havent been either. I just blew 3 fuses on a 15 minute ride home from work and it wasnt when the car started or anything, it was when i pulled quickly onto the highway that my guages all failed except the spedometer. Maybe the jerk back made some wire hit something but ive looked....guess its time to look again.

[itsbrokeagain]

Im running through these same issues as I write this. I did the redneck thing to get me home (less than 5 minutes) and in the process, I melted a ground wire for the ECU that runs into the fuse box. Fuse 10 had gotten so hot that it melted right next to it and shorted right to ground, blowing the 30A fuse in the process.


By the way, I had a guy tell me 'ah just put a 30A fuse in there and it will stop blowing'...and hes certified and works as an airplane mechanic..now that is scary.


So I cut the ground out and rerouted it myself to inside the engine bay. Checked the green/white wires from the fuse, and all are good, I peeled back the rubber boot going from the bottom of the fuse box to the car to check the wires to make sure none were melted, and other than the ground wire, all were fine.


After getting the whole car buttoned back up (what a PITA that rubber boot was) I put a new fuse in and check it out, and low and behold, she works. So I let her run for 15-20 minutes with the blower on, and shes perfectly fine.

The other guy I work with has this cool Buddy Amp tool that goes in place of the fuse and reads how many amps the circuit is drawing (max time on a shorted circuit is less than 10 seconds before it pops its own reserve fuse)...and while idling with the fan on and all that jazz, I got 4Amps at most. So I leave the shop, and down the block at the light, I go to shift into 1st and accelerate and bam, everything drops dead again.

My reverse lights have still yet to work this entire time. Which leads me to believe I might have a short in that end of the circuit, but the funny thing is that now that I realize it, I think everytime Ive popped a circuit, its either me shifting into 1st 3rd or 5th gear. Im going to pull the shifter boot up and have a looksee...the previous owner put a Z3 3.0 shifter in there, so maybe the wiring is getting rubbed around or something.

[itsbrokeagain]

I found the culprit. I pulled the connector for the reverse lights, and viola, shes not blowing the fuse anymore. Shoulda gave me a thought when i fixed the fuse, yet the reverse lights still didnt work.

[StereoInstaller1]

Sweet! Sounds to me like the classic "rubber boot ground" on the reverse light switch.

A new boot is like $12, BTW.

Good job!
Luke

[danl]

I'd glad older postings stay on here. I just had the same issue, and the fix worked. Many thanks.

[romeomike]

Me too. On my 91 318i, had no gauges except speedometer, no blower, no reverse lights, blown fuse 10. Did the K5/K7 removal test per ak96ss, and fuse 10 held. Subbed in some salvage yard relays with good results, and the blower motor works again as well. Thanks again.

[MCreally?]

your speedometer does not run on fuse 10, which is why you still have it. i would go to your reverse light switch connector C301 at the shifter boot. See if the short lies in the in the green/white wire or the blue/white wire. ALSO, check both sides of the connector to see if the short is on the transmission side or the body side.

these are likely culprits to your problem. if the short is in the green/white wire (body side) you are in for a headache. this wire is spliced to about 7 other systems. the blue/white wire is easily traced if you remove your driver and rear seat and move aside the carpet.