Help needed!

[davidtch]

I got tis strange prob wif my E39 that i hav no idea what it is caused by. On saturday, while accelerating on expressway, it went into limp mode. Battery sign, triangle sign, ABS & transmission failure come on. So, i exit d nearest exit & switch off. Restart. Still d same. So, i drove it 2 AAS (d nearest place 2 go on limp mode). Ingat bateri mati. Apparently, alternator overcharging. So, drove it 2 performance motor (1km away). Workshop tutup. Kena wait 4 Monday.Today, performance motor call me. Bateri mati. They haven't diagnose d problem yet. Have anybody encounter tis prob b4? What could b d problem?

 

[chili e30]

all the 39 sifu! pls help my bro!:frown:

 

[Seargent]

bro, new e39 owner also. Can't help.. no experience yet..

 

[leforte]

check your alternator voltage regulator. if its damaged/fused, the voltage will spike/dip, a small matter will just caused the battery to overcharged or not charged at all, your battery will act as a "?heatsink" to absorb all the excess current until it can take no more. there after it would fry the vital components like the DME (ecu) and EGS ( transmision ECU). a factory programed fail safe system will revert to limp mode to preserve the components but sometime it maybe too late, hopefully your dme and egs isnt badly shorted/damage beyond it fail safe point.

FYI Do remember after your repair that your cold air ductting to your alternator is properly attached and not stuck with leaves, heat is the primary cause of alternator failure.

 

[davidtch]

check your alternator voltage regulator. if its damaged/fused, the voltage will spike/dip, a small matter will just caused the battery to overcharged or not charged at all, your battery will act as a "?heatsink" to absorb all the excess current until it can take no more. there after it would fry the vital components like the DME (ecu) and EGS ( transmision ECU). a factory programed fail safe system will revert to limp mode to preserve the components but sometime it maybe too late, hopefully your dme and egs isnt badly shorted/damage beyond it fail safe point.

FYI Do remember after your repair that your cold air ductting to your alternator is properly attached and not stuck with leaves, heat is the primary cause of alternator failure.

Tks.

Performance motor changed d whole alternator & battery. I took back d old alternator & will change d voltage regulator. I will swap old alternator with new alternator in 2 yrs time.

 

[naharnms]

so, it is the alternator prob ya.. it happened on my e30 too, not only on e39..

Neeway, if the alternator not charging, that means all the power/ electrical gizmos is using solely on the battery power (which will not last long..), then the red battery indicator should light up. Normally, after you change to new alternator, the battery needs to be replace too (advisable) bcoz your battery might be 'over-drained' during the time when ur alternator not charging..

 

[davidtch]

It is the voltage regulator in the alternator. D alternator is generating 17v of power instead of 14v(i think). D problem is that it is very hard 2 find deep cycle battery or Absorbent glass mat in MY or Sg. These battery has thicker plate. So, can take higher charge from alternator.

 

[mohdrozali]

My onscreen computer indicates my consumption is 7.6km/litre. With price of petrol on the rise, have to do something about this quickly before my pockets get badly birnt. any views from anyone pls

 

[Jerman]

My onscreen computer indicates my consumption is 7.6km/litre. With price of petrol on the rise, have to do something about this quickly before my pockets get badly birnt. any views from anyone pls

bro,
The on-board Petrol Consumption Indicator may not be accurate. Do a full-tank to full-tank test yourself. Just a few simple check without getting into the technical parts......
1. Petrol cap: do you feel it's still tight? Seal OK?
2. Fuel filter: when was the last time you change it?
3. Spark plugs?
4. Air filter? Clogged with dust?
5. Have you changed to bigger tyres or rims lately?