Modifying Diesel Battery Tray

[Macca2801]

Originally Posted by kx steve

The problem with my battery dilemmas is, I don't use the jeep every day and when I do use it mostly its short trips.
The only time it does a long trip is when we go away.
My alternator puts out a 13.5 to a max of14.2 volts never seen it any higher.
I do charge it with a c-tek charger but not every month.

I bought a new D31a for $331.00


(Matt what C-tek do you have)

Probably being a tad optimistic with topping up the battery every month prob more like 2-4 months depending on what I've been doing. I'm like you, do lots of short runs and occasionally I will hear a slower than usual crank and then it's immediate ctek time. Biggest culprit is working on the car with radio cranking, this drains the battery very quickly so when I'm finished, ctek time!
I use an old 15A 7 Stage, basically this but older version....
http://www.ctek.com/au/en/chargers/MXS%2015
Matt.

[EugeJK]

Originally Posted by Macca2801

Some early JKs had incorrect charge voltages and they went through heaps of batteries until they mentioned it to the dealer and they re flashed the ECM to solve it.

Matt, do you have any reference or anything on this reflash? Tryed two local dealers and none could find any tweak in software to reduce charging voltage in ECM. Need to do this as my charging system puts out up to 14.8 and the batteries last only 3 years. Usually die during hot weather.

[drmadcat]

I think i have the same problem i tried to get a new one but the cheapest i found was $480 in Perth which seems really high. Wish i could find a cheaper one.

[samft]

Originally Posted by drmadcat

I think i have the same problem i tried to get a new one but the cheapest i found was $480 in Perth which seems really high. Wish i could find a cheaper one.

~$350 on ebay, free delivery

[samft]

Originally Posted by EugeJK

Matt, do you have any reference or anything on this reflash? Tryed two local dealers and none could find any tweak in software to reduce charging voltage in ECM. Need to do this as my charging system puts out up to 14.8 and the batteries last only 3 years. Usually die during hot weather.

where are u measuring this voltage?
across the battery?

try measuring the voltage that the ECU is picking up,
you might be getting a voltage drop to the ECU in which case the ECU will ask the alternator to compensate and put out more volts

Voltage should almost identical between alternator output, battery and ECU

I had a problem where the alternator was cranking out volts but the battery and ECU were experiencing ~0.5-1V drop, all fixed now though

[EugeJK]

Originally Posted by drmadcat

I think i have the same problem i tried to get a new one but the cheapest i found was $480 in Perth which seems really high. Wish i could find a cheaper one.

$355 lowest I saw here: http://www.ebay.com.au/itm/OPTIMA-YE...-/141708198235

Note self-pickup option at nearest Woolworths or BigW.

[EugeJK]

Originally Posted by samft

where are u measuring this voltage?
across the battery?

try measuring the voltage that the ECU is picking up,
you might be getting a voltage drop to the ECU in which case the ECU will ask the alternator to compensate and put out more volts

Yes, across the battery terminals.

Fair point, do you know which pin on the ECU connector? I don't have a schematic for the electrics. Just a page of the corresponding wires would suffice if you have it bro