battery

[shockercbh]

I recentley replaced my battery thinking it was bad.I drove about 70 miles then all the tachs went hay wire then the car died.I took the alternator off and had it tested.It turned out it was bad.I can jumpstart the car from the positive terminal under the hood.It wont jumpstart from the battery in the trunk.Do you think I have a faulty ignition switch?

[johnnyBgood]

Originally Posted by shockercbh

I recentley replaced my battery thinking it was bad.I drove about 70 miles then all the tachs went hay wire then the car died.I took the alternator off and had it tested.It turned out it was bad.I can jumpstart the car from the positive terminal under the hood.It wont jumpstart from the battery in the trunk.Do you think I have a faulty ignition switch?

Negative........ When you jump start from the positive terminal under the hood, you are supplying a more direct current to the starter, then from the trunk.


jb

[darkhorse737]

^ +1

[shockercbh]

My battery is new and has a full charge.The alternator is new also.All the lights work.I can start the car with a jumpstart .I turn the key I get nothing.Can anyone tell me what the problem could be?

[johnnyBgood]

Originally Posted by shockercbh

My battery is new and has a full charge.The alternator is new also.All the lights work.I can start the car with a jumpstart .I turn the key I get nothing.Can anyone tell me what the problem could be?

Was everything wired up correctly, battery cables to the alternator?

jb

[shockercbh]

Everything is hooked up right.I took the car about 20 miles down the road to see if the battery would stay charged.The alternator is charging the battery ok.Since I can jumpstart it,would that eliminate bad ignition switch and starter?

[johnnyBgood]

Originally Posted by shockercbh

Everything is hooked up right.I took the car about 20 miles down the road to see if the battery would stay charged.The alternator is charging the battery ok.Since I can jumpstart it,would that eliminate bad ignition switch and starter?

When you say jump start, you don't mean you are jumping out the starter........

you are just connecting jumper cables to the positive terminal in the engine compartment & to ground......


jb

[shockercbh]

Im jumping it from the engine compartment positive post.

[johnnyBgood]

Originally Posted by shockercbh

Im jumping it from the engine compartment positive post.

So....when you are not jumping it, you turn the ignition key & nothing happens......no clicking or turning......correct?

But.....when you jump it, it starts normally by turning the ignition key...

Sounds like, it might be a fusible link.....issue....I'll check in my Bentley Service Manual

jb

[johnnyBgood]

Ok......in my Bentley, it says to check for battery voltage between ground & terminal B+ at back of alternator. Then turn ignition on and check for battery voltage between D+ and ground. If voltage is not present at either point, check wiring faults.......see. Fig. 3 page 121-5

so if you don't have a Bentley......here is a link to download it......thanks to Torque!


http://www.bimmerwerkz.com/forum/3-s...pdf-67601.html

jb

[darkhorse737]

loose connections and bad grounding is the probable cause.

in rare cases, where the battery has been maintained badly(left alone to leak) the corrosion will seep through the positive line and cause more resistance in the positive wire.

You can test for voltage drop - take a voltage reading at the battery and another reading, at the positive terminal in the engine bay. if there is a difference, concentrate ur effort in the lines leading to the battery

I will take a chance and clean the battery terminals, pour hot water over the terminals and clean 'em right. follow the ground wire(big brown wire to see it is fast on to the body).

Then, check also engine ground - big brown wire u will see on the right side of ur engine at the motor mount to the body;-)

[shockercbh]

Thanks for all the help.I will let you know what I find this weekend.I do believe I have a short.

[rubby.simpson45]

My friend battery is dam new and was charged fully , even the altenator was also new , the car was being started with a jumpstart, and all the lights also works , but when i turn the key , it was not being start , Icouldn't understand wht may be the problem can any one answer?????


Rubby.simpson45
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