Battery light flickers now and again

lionatus · 19th August 2021, 09:55

Mickboy was great and sent me a power steering pump which did the job. My battery was 7 years old and was goosed, noticed when big battery charge failure came on but had enough juice to get home. Charged and charged and charged but couldn't get above the medium charge to hold on the battery. Voltages were all fine when it was idling and under load though which was weird.

New battery in flashed charge warning again and I'm thinking not the alternator too! But its not come on since after 3-4 smallish journeys with a battery pack in the boot just in case. But, the smaller non0message centre actual battery warning flickers a bit which I've never seen on my ZT diesel before. Haven't been able to check connectors yet as I have no access and will have to borrow a lift at the garage as I'm not lying under the car next to a main road as busy as the M6. Any ideas? Is it likely to be because of the new battery changeover, is the alternator goosed by maybe contaminant from the old leaky steering pump or connections. Would trying to do a top down cleanover of the alternator help i.e. maybe with electrical contact cleaning spray?

HarryM1BYT · 19th August 2021, 10:48

Quote:

Originally Posted by lionatus

Any ideas? Is it likely to be because of the new battery changeover, is the alternator goosed by maybe contaminant from the old leaky steering pump or connections. Would trying to do a top down cleanover of the alternator help i.e. maybe with electrical contact cleaning spray?

That problem rings a bell from a few years back.

After much investigation, it turned out to be just a poor connection or similar, something to do with a failing wire or connection to the engine ECU. A battery voltage sensing problem, rather than an actual battery or alternator issue on the diesel.

You could confirm it by wiring a voltmeter to your battery, so you could monitor it as you drive. Depending on load, it should always indicate above around 14.2 to 14.5v.

You need to do a search through the forum, unless someone remembers and can provide a link.

lionatus · 19th August 2021, 21:13

I'll try the connections. New battery worked but I can see flickering when revs are above 1400ish. Not sure if its so faint that I just cant see below that but its there, maybe connections due to the voltages being ok on the multi-meter. Who knows brush replacement?

Quote:

Originally Posted by HarryM1BYT

That problem rings a bell from a few years back.

After much investigation, it turned out to be just a poor connection or similar, something to do with a failing wire or connection to the engine ECU. A battery voltage sensing problem, rather than an actual battery or alternator issue on the diesel.

You could confirm it by wiring a voltmeter to your battery, so you could monitor it as you drive. Depending on load, it should always indicate above around 14.2 to 14.5v.

You need to do a search through the forum, unless someone remembers and can provide a link.

COLVERT · 21st August 2021, 19:57

Quote:

Originally Posted by lionatus

I'll try the connections. New battery worked but I can see flickering when revs are above 1400ish. Not sure if its so faint that I just cant see below that but its there, maybe connections due to the voltages being ok on the multi-meter. Who knows brush replacement?

If it really is the brushes then flashing indicates arcing.--If so, quick replacement is required as the arcing will quickly eat the copper slip rings away.-----

lionatus · 22nd August 2021, 00:34

Ill be doing this in the next few hours if I can, with a break to make the oldies breakfast. I still think its a full replacement but Ill try everything just to see. I have to I have the addictive personality just to know. I replace with a full unit and Ill always wonder what if....

\Its a curse and a blessing; it means I fail lots but it also means I succeed lots and those successes are worth framing as they are priceless.

BTW Colvert ty for the advice I had no plans to drive much anyway due to the fact the battery isn't charging; We cleaned it with brake fluid to see what happened and the fault disappeared for 12 hours. I'm thinking not brushes but Ill do it as I planned to. Every avenue leas to more experience and perhaps unforeseen benefits.

Regards, Alan

Quote:

Originally Posted by COLVERT

If it really is the brushes then flashing indicates arcing.--If so, quick replacement is required as the arcing will quickly eat the copper slip rings away.-----

19th August 2021, 09:55	#1
lionatus Loves to post MG ZT-T Join Date: Nov 2014 Location: Hawick Posts: 350 Thanks: 46 Thanked 22 Times in 22 Posts	Battery light flickers now and again Mickboy was great and sent me a power steering pump which did the job. My battery was 7 years old and was goosed, noticed when big battery charge failure came on but had enough juice to get home. Charged and charged and charged but couldn't get above the medium charge to hold on the battery. Voltages were all fine when it was idling and under load though which was weird. New battery in flashed charge warning again and I'm thinking not the alternator too! But its not come on since after 3-4 smallish journeys with a battery pack in the boot just in case. But, the smaller non0message centre actual battery warning flickers a bit which I've never seen on my ZT diesel before. Haven't been able to check connectors yet as I have no access and will have to borrow a lift at the garage as I'm not lying under the car next to a main road as busy as the M6. Any ideas? Is it likely to be because of the new battery changeover, is the alternator goosed by maybe contaminant from the old leaky steering pump or connections. Would trying to do a top down cleanover of the alternator help i.e. maybe with electrical contact cleaning spray?