348 Electrical Question..

Ok here is a bizarre situation and the back story behind it…

Few weeks back I was out for the weekend and when I returned to my car a few hours later the car would not start. The lights were about 50% and there was the “click” but not enough power to turn over. I wrote it off to my stupidity of leaving a light on or something, got a jump start after I located the jump terminals in the rear of the engine bay and drove home with no issues. Several weeks passed and there wasn’t even a glitch.

This weekend, I stopped by a carwash to vacuum out the 348 and clean the interior. Had a few phone calls come in and casually cleaned and did my thing for an hour or so. When I went to leave the battery was nearly flat. The dash lights were barely a 10% on the dash. I thought to myself that I must have left a light on again while I was on a call or the doors were open to long (after all it was an old battery that I just hadn’t gotten around to replace). Had a friendly car washer jump me and I was off and running. I figured that I would put the new battery in the car the following day. 15 min later on the drive home, was sitting at a stoplight just a mile or so from my house and the car just stopped at the light. I think that the cooling fan or something kicked on and took all of the power. But needless to say I was dead in the water. Had my neighbor drive over and help me boost alive again. Fired it up again (after several attempts to find a good connection) and as soon as I turned on my lights to see, the car died again. Started it again and just raced home on the back road with the lights off.

The following day, I pulled off the front driver tire, pulled out the old battery from its spot (which is a dumb place for a battery IMHO) and put in the brand new one that I had purchased a week earlier. Got the car all buttoned back up and turned the key. All lights in the car were 110%. Let the relays charge for a moment and then turned the key to start. At the moment of starting there was a simple “click” from the back and then all of the lights went from 110% down to about 10% just like I had the old battery in there. Then in a moment all of the power was totally gone short of a faint pathetic buzz from the dash when you turned the key.

Now I know the battery is brand new so there is power in the front.
Checked the little power cut off knob under the bonnet and that was functioning in the correct position, and then took a novice look in the rear to make sure that all of the connections were secure. The jump terminal has 3 leads connecting there. I would assume that its one from the battery, one to the alternator and one to the starter. All seemed very tight and secure on both sides.

So with all of that said any suggestions to what would cause the power shortage? My best guess is either some kind of grounding issue somewhere or maybe that relay terminal in the back isn’t moving the power from the battery into the other posts for starter/alternator?

Thoughts from anyone?

 

I had a similar issue with mine. Brought it to the dealer several times but no one could find the problem. In the end I traded it in (same dealer I bought it from) for a 360. Their best guess was some sort of sensor, of which there are 2 (one per 4 cylinders) but I forgot which sort of sensor. We never got to replace them. Sorry that I am of little help here...but the sensors (lambda maybe) are something you might want to have checked.

Of course if the battery was really dead then there wasn't a sensor issue. However....in my case I just waited a minute or 2, and kept trying to start it until at some point it did. What I'm thinking is, it could be coincidence that it started when you jump started it, leaving you to think that it's a power issue. I'm just saying this because it seems strange that the car just switched off at a traffic light. Normally you would first get an abs error if the power goes down gradually.

 

Mmhh thinking now that what I wrote makes little sense; you did get the lights down in the dashboard. Sorry, must be a power issue indeed.

 

I agree.. the 3 times that I have had to jump it have all been successful once we got a solid connection. Im thinking that there has to be some kind of glitch in that junction terminal or some kind of wire issue there?

Oh well.. my car and my money go back to the shop for a diagnostic if I cant figure it out

 

With that being said.. I tested the Volts at the charging posts in the back and the power is making it to that point. So there is some kind of disconnect from that point forward to the components. Does anyone know where the power grounds from there forward? I'm thinking if jump starting it with a direct connection to the positive post and a ground to the chassis fires it up, there must be a problem with a ground location?

 

I had a very similar situation and finally traced the problem to the actual cast metal fitting that bolts onto the battery post. Everything read 12 volts when the key was turned to aux, but the minute you asked for starting power, the battery cable terminal became a big resistor. If you get to the passenger-side fuse box, then remove the one or 2 bolts that hold that down, you can move it out of the way and you'll see a bus bar and (I think) three big wires bolted to it. If you get your car to not start again, then disconnect the + battery terminal, and instead run a jumper cable from the + battery terminal to one of the bolts on that bus bar, and see if that works. If it does, cut the cable end off, and for 2 or 3 bucks get a replacement at Autozone. If it doesn't work, try bypassing the neg. battery terminal instead.

 

That symptom sounds a lot like a very poor connection at one of the two battery terminals.

 

could be oxidation at the two battery terminals....remove it and clean it up with a wire brush/sand paper and see if the problem goes way....

 

In my case the oxidation was inside the terminal where the wires went into the fitting. Looked OK on the outside, but apparently big problems inside.

 

Hmm.. pnicholasen.. I certainly can try to find that location and look for that. Good suggestion there.

bikz: I don't think it is oxidation.. when I changed out the battery for the new one I cleaned off the leads and of course the new battery was spotless. But I can look again?

yelcab: I will double check my connections also. Was pretty sure that those were tight when I put the battery back in the slot.

Thank you all for your suggestions... any others is greatly appreciated! Ill keep checking off the list as they are made!

I tested the Volts at the back of the car and I got a little shy of 12v. Chances are the reason it wasn’t the full 12.5 is probably because the battery sat on the store shelf for who knows how long and then for 2 weeks on my garage floor but the power is at least making it to the back of the engine bay anyway. But if the cable is a "resistor" as you say when I got to crank the power, it may be trying to fool me!

 

Update???

 

My positive cable looked corrosion free and fine but I ended up threading in a whole new cable (not too hard)and it fixed my starter problems totally. They corrode internally.

 

The voltage drop from the battery + terminal to the starter is killing you. THe cable is either internally corroded, or corroded within inches of the battery terminal, or corroded inside the terminal of the cable. You will need to find where that corrosion is, clean it, or replace it.

 

Sorry for the delay guys.. haven't gotten an update yet! The 348 has been in the garage since our Labor Day holiday weekend. I hope to tear into it and test the volts at all of the points of contact to see if I can isolate it. I do appreciate all of your advice and points to ponder, I will let you know what I find out as soon as I can get under the beast!

You guys are all awesome!

 

When checking voltage levels make sure the circuit is under load, example if checking the starter make sure it is turning over. The reason is many wiring problems will to show up under static conditions due to low current flow in this condition.

 

That is a good point.. I guess I will have to recruit a neighbor to sit there and turn the key!

 

No one mentioned the disconnect coupling, the one that sits just above the battery cover.
I assume you checked this for corrosion?

 

Any of this any help?

http://www.ferrarichat.com/forum/348-355/202861-348-starter-relay-modification.html

 

I actually have read that post about the starter modification. That may be a little above my pay grade to install. However a new twist to the story is attached a trickle charger to the rear of the car to see if I could get it started and test the volts and upon doing so I heard a horrible buzzing sound from the passenger footwell. Now I know the fuse box and the extra relays are located there. Maybe my ignorance of understanding how the electrical current flows from the battery through the electrical system all the way to the starter at the end point but I'm wondering if that relay box is faulty at this point or one of the individual relays. What is odd, I've tested all points from the battery to the back of the car. Both sides the electrical cutoff switch under the bonnet, at the power cable at the starter, and anywhere else I can think of. I'm getting at least 11.6 v at all locations.

So if that junction box in the footwall was faulty, I would assume it would not let any charge through from that point to the rear of the car? Short of disassembling the entire unit, is there a way to test it and see if that is where the roadblock is? I don't believe based on the diagram that any of the relays in that location have anything to do with ignition problems?

I apologize in advance if there are typos there. Doing this on the phone is not easy lol

 

Also am not familiar with this battery coupling you're referring to. In my 1994 car battery is located in front of the front driver side tire rather than in the engine bay where the prior years had it located. From what I can see the battery cables go directly from the battery into the body work on the car. I did not happen to notice if there was another junction there. Considering it barely has enough space to fit the battery, I don't know where they would put it!

 

Diagram for you but check your engine no as there's a another diagram if you press next

http://www.eurospares.co.uk/partTable.asp?M=1&Mo=434&A=1&B=23684&S=

 

Another place to check is if there is an electrical connector under the Air filter box. My 89 had a weird (yep, technical term) cone type connection that when I pulled it apart (to replace the cable to the rear mounted battery) had white arc soot all over the mating faces. The new cable from Ricambi (once again saved the day) had a better design and was $1200.00 cheaper than good ole' FNA. Because the cable from the rear battery is only 5ft long to the starter, I was surprised to find a connector. YMMV.

Jeff Pintler
89 348tb, 86tr, 99 360 3-pedal

 

Regardless to if any of these diagrams fix any of the issues, this is an AWESOME resource for sure. I am definitely going to bookmark that one.

I have about given up my hunt, partially due to my time and mostly due to patience. Im just going to give it to my Ferrari guy to do it. The cost will be worth the couple hours he takes to find the issue and replace it than it would be for me to take a month of wrench turning, cussing, banged knuckles and blood. I don't have enough patience for it. I guess we all cant be the best at everything eh? Haha

 

I think this is the connector Jeff is talking about - I cleaned mine when I replaced my battery the other day

Battery Replacement on Early Rear Battery Cars

 

sorry wrong link - its the last pic in this one - its the big red connection and just twists and pulls apart

Bosch WR-1 Hard Start Relay Fitting