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156 V6 Battery

3K views 14 replies 6 participants last post by  Bigpaul125 
#1 ·
Hi, the battery on my 156 2.5 failed to start the car the other day, and I'd like some advice on the recommended procedure for charging/changing so as not to cause the problem that I had when the current battery was fitted back in 2014.

Back in 2014 we were on holiday in Belgium when one morning the battery was dead (sudden failure, because the car had been used daily and had been fine the day before). So, called the recovery wagon and the guy did the usual and "jumped" it from his onboard battery pack. Car started, but was undrivable because it wouldn't rev higher than idle (as though the throttle was disconnected), so he transported us to the (relatively) local Alfa dealers. They were very efficient and fitted a new battery and (I believe) had to reset the ECU, after which it was fine and we continued our trip.

Fast forward to today, and I'd like to avoid similar problems with the ECU! Before, I can only think that the power surge provided by the jump start had done something nasty to the ECU codes (I think I read somewhere afterwards that these cars shouldn't be jump started from another car using jump leads)? So, with the car in the garage, would it be safe to charge the battery in situ (i.e. still connected) with a standard "home use" car battery charger - would that provide a mild enough charge rate not to cause a problem? Or, if I disconnect the battery and change it for a new one, would I similarly lose the codes and require a reset?

Any advice would be very much appreciated....!
 
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#2 ·
If you have a smart charger (like the CTek) then you can charge without disconnecting just fine, I run a cable out to mine to do just that as I installed a connector inside the car so I don't even need to lift the bonnet.

If what you have is a regular trickle charger tho, I'd disconnect the battery (-ve should do) and connect the charger to the battery. Once fully charged then you can reconnect the battery. Does sound like a new battery would be a good idea tho but 2014 to now is a pretty good run tbh.
 
#3 ·
I think all you really need to do is when you replace the battery to leave the key in the run position (but not start the car) for a few minutes, or less for the throttle body to calibrate itself and find idle. I know when I reconnected a battery and started the car quickly before the TB had a chance to calibrate itself the car idled but did not respond to the accelerator pedal.

Usually you can hear the throttle body click and move around as well as the climate air system as it finds it's parameters following a battery disconnect/reconnect procedure.

You can jump start cars. It is in the book iirc.

Some battery chargers should only charge batteries when they are removed from the car. It should be in the charegrs instructions.
 
#5 ·
Great, thanks for your advice. Good to hear that I should be able to disconnect/reconnect the battery without suffering the "idle only" problem I had before, by leaving the key in the "run" position for a while and allowing the system to reset itself before starting.

I guess I'll need to source a replacement battery. The current Alfa brand lasted quite well, but will be more difficult to source and likely more expensive - are Bosch and Varta still the recommended options on a price/quality ratio?

To replace the battery, does the array of fuses connected to the positive terminal simply unbolt and swing out of the way....looks a little more daunting than the typical battery change?

Thanks again!
 
#7 ·
I guess I'll need to source a replacement battery. The current Alfa brand lasted quite well, but will be more difficult to source and likely more expensive - are Bosch and Varta still the recommended options on a price/quality ratio?
Yes, Bosch or Varta, same battery with different names on them.
096 size
So Bosch S5008 or Varta E44.
Tayna usually has good prices
ie:

Exide worth a look too:

To replace the battery, does the array of fuses connected to the positive terminal simply unbolt and swing out of the way....looks a little more daunting than the typical battery change?
There may be a couple of small screws holding it to the battery, but other than that it will lift up off of the battery with the +ve connector.
 
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#6 ·
Battery wise i have had a Halfords battery from their silver range on my diesel GT for 6 years now, they guarantee it for 50,000 starts or 5 years, it was around £100 but has never let me down. I will be getting one for my 156 when the time comes as well.
 
#9 ·
If you do go for another kind of battery, just make sure that the positive and negative terminals are in the right places.

I would think anything with the current specs that your current battery has will be sufficient.

You just undo the small nut that holds the fuse box on on the battery terminal. Then you live up the whole fuse box thing up and off, but it's still connected to the wires. Make sure you don't let your spanner or socket touch the car though when undoing, and undo the negative terminal first. There's a strap for the battery held on by one nut. Then the battery should just lift out.
 
#10 ·
you'll likely also need to remove the air intake hose, be careful not to stress the flexi section too much in case it splits, check it over well too before refitting, any splits and you'll get running issues/back-fires etc, been there and ended up replacing the entire induction tubing with silicon that I cut to suit.
 
#11 ·
Thanks again for your replies, all very helpful.

Just one thing I've spotted whilst searching for batteries - some suppliers seem to list a different size (height) battery for the V6 compared to the TS and diesel models (ie 175mm vs 190mm). Is this because the 190mm battery is too high - I'd like to go with the 190mm batteries because they seem to have higher A/H and CCA ratings. I checked, and my current (Alfa branded/fitted) battery is indeed 175mm high (72 A/H 660 CCA). Can anyone confirm that the 190mm batteries will fit in the V6 engine bay and, if so, why Alfa seemingly recommend the 175mm battery for this model?

Thanks!
 
#12 ·
Diesels usually need higher CCA and A/H ratings from what I know. It might fit, but if the last battery operated fine, why change?

As for TS engines with the large battery. That beats me. Maybe it's something to do with the coolant expansion tank, as only the 2.5 V6 has the coolant tank on the side near the battery.
 
#13 ·
If I recall, it'll fit but the clamp won't reach far enough with the taller battery so it'll be able to shift around on the tray. I ended up with the taller one when I went and bought a new battery years back. At that time I think the Bosch listing was either incorrect or confusing (or just misread) so the sales guy gave me the taller one, easy exchange for the right size tho when I returned later the same day.

Currently running a Yuasa Silver in my v6, been good for 3 years so far. Only problem I found was the -ve terminal doesn't clamp tight so shimmed it with some lead at the time, have since replaced the clamp which bolts up nice and tight now.
 
#14 · (Edited)
I'd forgotten about the different strap length issue.
It seams some had straps for 190mm high but others 175mm high. Each owner will need to check what they have.
For the 156 V6 & Diesel:
190mm high is an 096 size (eg Bosch S5008 / Varta E44)
175mm high is a 100 size (eg Bosch S5007 / Varta E38)

To confuse the issue even more, some 175mm high batteries are labelled "096/100". But a 175mm high isn't an 096 size, it is a 100 size.


All 156TS used the 027 size, which is 190mm high (eg Bosch S5005 / Varta D15).
 
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