Positive terminal in engine bay

[skunka]

Yesterday, after band camp was over a student's car wouldn't start. I drove over and popped both hoods and hooked up my cables to the positive terminal and to bodywork, and then to the student's car. When I connected the clamps to his battery I didn't get any small sparks like you usually do. Sure enough, his car wouldn't start.

A co-worker was leaving at the same time and came over and we were able to get the kid's car jumped and he was on his way.

My bigger concern is that the positive terminal under my hood wasn't working. Is there a fuse that connects the terminal to the battery? I've never had a need to use the positive terminal since I've owned the car. But If the time ever comes, I'm glad I discovered this now, rather than when I need a jump!

Thanks for your help!

[CallMePuff]

Yesterday, after band camp was over a student's car wouldn't start. I drove over and popped both hoods and hooked up my cables to the positive terminal and to bodywork, and then to the student's car. When I connected the clamps to his battery I didn't get any small sparks like you usually do. Sure enough, his car wouldn't start.

A co-worker was leaving at the same time and came over and we were able to get the kid's car jumped and he was on his way.

My bigger concern is that the positive terminal under my hood wasn't working. Is there a fuse that connects the terminal to the battery? I've never had a need to use the positive terminal since I've owned the car. But If the time ever comes, I'm glad I discovered this now, rather than when I need a jump!

Thanks for your help!

I ran into the same issue and thought that my terminal wasn't working either, but it turned out that my ground was bad.

I don't know the answer to the fuse question off the top of my head, but I usually ground the jumper cables to my alternator. There's a spot on the frame that the clamp fits on if you really squeeze it. I've never had any issues with this location.

Where have you been grounding?

-edit-
You can take a voltmeter to see if the positive is getting power.

Sent from my Nexus 6P using Tapatalk

[skunka]

When using a trickle charger on my other e34, I usually ground to one of the strut mount nuts.

Now that I'm thinking about it, when I tried trickle charging it before, I did connect the negative to one of the hood hinges and it never charged... maybe that is insufficient ground.

[fo3]

Yesterday, after band camp was over a student's car wouldn't start. I drove over and popped both hoods and hooked up my cables to the positive terminal and to bodywork, and then to the student's car. When I connected the clamps to his battery I didn't get any small sparks like you usually do. Sure enough, his car wouldn't start.

A co-worker was leaving at the same time and came over and we were able to get the kid's car jumped and he was on his way.

My bigger concern is that the positive terminal under my hood wasn't working. Is there a fuse that connects the terminal to the battery? I've never had a need to use the positive terminal since I've owned the car. But If the time ever comes, I'm glad I discovered this now, rather than when I need a jump!

Thanks for your help!

I've got an older model so my battery is in the engine bay so I can't check myself, but from what I've read: Is your positive terminal near the diagnostic plug/fuse box? If so I don't think there's a fuse as it connects to the start motor positive directly below. If yours doesn't work maybe someone disconnected it from the starter motor?

[skunka]

Is your positive terminal near the diagnostic plug/fuse box?

yes

If so I don't think there's a fuse as it connects to the start motor positive directly below. If yours doesn't work maybe someone disconnected it from the starter motor?

I will check this. There was a point when I was doing work on the throttle cable so things may have gotten moved around a bit.

[moroza]

There is a fuse between the B+ terminal and the battery, but it's the main fusible links (two), and if those go you'll have a lot more not working than just the jumpstart post. I agree with the above - probably a bad ground. I usually use the rear hood latches near the fusebox and e-box.

[fo3]

Well yeah, there is a fuse but it's the main one that also goes to the starter, so if it was open circuit then your car wouldn't start either.

I guess check for volts (with multimeter or check light etc) on the terminal against a good ground (like the engine) before digging any further

[tantumaude]

I had an interesting issue similar to this after my alternator caught fire--basically, one half (passenger side) of the positive block worked, the other half (driver's) did not. I couldn't see any crossover points, so I have no idea to this day what caused that problem.

[south42]

I am guessing you just did not have a good ground. I just take off the rear seat and jump it from the battery.


Andy