Charging Problem ???

91 348TS
Thought I'd get 1 last drive out of the 348 before it goes into hibernation(winter). Started up fine(lots of juice), drive off down the road, oil pressure maxed out, speedo not moving, water temp not rising, clearly have a fault... most probably a ground issue. Sunny weather, so I continue a bit...Then the 2 check wallet lights hit on, along with an audible beeping. Pull over, check things out, decide to head home, but... battery does not have enough power to start??? Sit for ten minutes, start up(barely turning over) and head home... car stalls into the driveway. Leave it for another 20 minutes, hook up a battery tester, battery a little low but starts car up again ... check for charging, nope same voltage as engine off! Ok, my alternator must be screwy.... Alternator tests out well(reputable alt rebuilder) ((BTW.. he was impressed with Ernie's part#s for reg & rectifier... I was prepared!!LOL!) More searching... was going to look for bullet connector under airbox, but remembered seeing a solid new grd from battery to Cutoff Switch to engine casing. (PO used a frigging RED colored cable as a ground). Thank god I a little cautious about recharging batt... checking for positive/ then rechecking. Anyway, alternator is back in tonight... not sure what to look for next. BTW fault code 1122 (Battery Voltage) will be back at it tomorrow...
My thinking is it must be some grd connection as my dash meters are non functional(all of a sudden), battery doesn't see an alternator charge, yet it checks out on a bench test??? Is there other bullet connectors that might be loose, and therefore not sending back a charge from the alternator? Maybe I'm just tired... Any thoughts appreciated....

 

I forgot to mention the red charging (idiot) light never lit up???? Only on the reg startup for seconds(normal). If it were just the dash meters, I would assume a plug has come loose, but this no charging issue, with no warning lights, other than the check wallet lights going off with battery voltage code 1122, and drained battery fairly quick... I need some thoughts

 

Stick a voltage meter on the battery, 12 volts with engine off and around 14 volts running. If not then you have a charging problem. Use the 12 volt power socket if you like.

 

Thanks Mike. that was the1st thing I did.... 12V at battery, no change with engine running! Immediately thought alternator was toast.... Removed alt, had it checked by a reputable Alt Rebuilder and alt checked out well. I put it back in last night, will check again this am.

 

See if you can pickup volts direct off the alt, otherwise u r looking at the cables

 

OK... went out this am, check battery voltage..12V, started car... reading just a touch lower, so my car is not charging!!! It's a little concerning that my gauges are on the 'fritz' at the same time, as well, the alt seems to bench test well!! Is there anything else that could be causing the alt charging not to make it back to the battery? I'm stumped on this.... Also, my 'idiot' dash batt light is not illuminating when key is turned on. Could it be that the bulb, or connection to dash, is upsetting the alt charging back, or maybe burnt bulb might not allow alternator to start charging??? My brain is working overtime now... I'll go out after lunch and pull the dash... The way the workshop manual posts up the elec diagrams is something to behold!!! I guess I'll have to print them all off, then 'paste' them together...

 

Hmm, car is on my lift, I'll try that 1st, after lunch...

 

The voltage at the charger is transferred to the battery via the connector at the right hand side of the engine compartment. Check for good connection and good grounding there.

 

Surely a loose ground somewhere?

 

Hate to sound stupid, but, where in the right side engine compartment would this connector be? thanks...

 

I think he's talking about a later car. IIRC the alternator charge wire goes to the main terminal on the starter on my '91, but I'm not 100% positive (pun intended).

The fact that your gauges aren't working is a puzzler. I can't think of anything in the charging system that would affect the cluster but I haven't had to diagnose that problem before so there may be something I'm missing. On some cars the alternator does not charge when the alternator light is not connected so that could be the case here. Have you checked the fuses?

The nine pin(?) connector on the left side of the engine bay might carry the charge wire signal so you might check it as well, but I don't think even disconnecting completely it kills all the gauges.

First thing I'd do would be to check any and all fuses for the cluster. If indeed the alt requires the charge light to be connected it could be something as simple as a blown fuse.

 

Thanks Mike. Car being new to me, I'm not sure where this 9pin connector is... as I'm typing, I haven't looked hard yet. I believe you may be on the right track. The Oil pressure gauge is reacting the same as a missing grd in the engine bay(had that happen earlier when new to me). The gauge is getting the 12V, and needle sits Maxed out. Speedo and Temp sending wires may also be somehow disconnected... Does anyone have a pic or description of where this 9 pin connection is?
I did verify that the Alt has 12V going to it. Pulled the idiot lights out of the dash, all good! I'm leaning towards this connector, maybe the wires in it feed my dash gauges, as well as possibly the charging light(dash) wire to 'excite' alt may be in this connector as well. I'm going to print off and piece together the entire wiring diagrams(PITA). Have to get the car back on the hoist to look for this connector, or is it in the upper engine bay, left side?

 

Top side of engine bay mounted to the rear subframe on or near the left shock tower. Easily accessible from the top. The pin-out was kindly provided by Miroljub in the last post here: http://www.ferrarichat.com/forum/348-355-sponsored-bradan/515692-348tb-engine-bay-connector.html. As you can see, they're related to the very items you're having problems with.

Do check all the fuses as well if you don't find anything wrong with the nine pin connector.

 

MIKE... YOU ARE MY HERO!!!! I just found the connector...and came in to report all is well and I see you posted the location... Here's the lowdown. The 9pin connector was just sitting there, looking like it was connected. Well it wasn't, pushed it in and verified , all is good. Charging, and gauges fine, I'll assume speedo good, as I've got some work to put this car back together to TEST(meaning beat on it). Upon closer inspection, there is a plastic round 'screw on' retainer. Well that ring of plastic had 5/8ths of a ring with 3/8th broken off, allowing it to loosen. My uneducated guess is last engine out, retainer broke and they just shoved it back in... I thank you all for you help. Weather's cold, but sunny out, just won't finish putting it back together before it gets dark. Tomorrow's another day. God it feels good! LOL!

 

Awesome! Very glad it was such a simple fix.

 

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Another thread with a happy ending! Good job guys.

 

m.stojanvic... excellent diagram.... certainly explains the total headache I was having... what a forum!!
thanks again guys
best,
Sandy

 

Do not forget to change the bulb if it does not light up with key first turned on.