Flashing charge light

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Eratosthenes
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Flashing charge light

Post by Eratosthenes » Mon Jun 14, 2021 8:13 pm

All packed and set off for a few days.
Stopped for some petrol after about half an hours drive,
on leaving the garage I noticed the charging light was flashing.
Drove home without any problem but the light is still flashing.
The van is a V6 petrol. I have a leisure battery fitted which is
3 or 4 years old and the main battery slightly younger.
Just going back out to the van to take some readings on both batteries.

Any info really appreciated.


Main Leisure
12.69 12.65 engine off
14.34 14.32 engine running
14.32 14.31 engine running with headlights om
14.27 14.21 engine running headlights and a/c
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g8dhe
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Re: Flashing charge light

Post by g8dhe » Mon Jun 14, 2021 9:06 pm

The charge light is to indicate if the alternator is functioning and charging the starter battery, its driven directly from the alternator to the dashboard light.
Do you have an old style Split Charge Relay I wonder for charging a leisure battery, the old style set ups used the same signal to operate the relay so that might be cause if something was wrong ?
Geoff
2001 Aero V6, AFT, full side conversion.
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Eratosthenes
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Re: Flashing charge light

Post by Eratosthenes » Mon Jun 14, 2021 10:03 pm

Geoff,
Thanks for the reply.
I am not sure if I have the old or new style split relay, its about 4 years since I purchased it from Karl.
Do you think it is worth disconnecting the leisure battery or would you have to remove the relay to
see if it makes a difference?
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Re: Flashing charge light

Post by g8dhe » Mon Jun 14, 2021 10:07 pm

If it came from Karl then it will be a Voltage Sensitive type and won't be going anywhere near the Alternator wiring as such so very unlikely to be the cause of the problem.

When you say its flashing, what speed of flashing or do you mean random flashing ?

All the voltages you quoted sound about in spec. as well so nothing odd from them.
Geoff
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Eratosthenes
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Re: Flashing charge light

Post by Eratosthenes » Mon Jun 14, 2021 10:26 pm

Geoff,

When I turn on the ignition all warning lights are on as expected When I start the engine the charge light immediately goes off for about a second or so then starts a regular on off pattern, - about a second or so on and then a second or so off.
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g8dhe
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Re: Flashing charge light

Post by g8dhe » Tue Jun 15, 2021 8:27 am

That's an odd pattern for that light then, one which I can't see an obvious explanation.
Is it fully On/Off no dimming of that or any other light ? No engine speed variations ?
Are you able to check under the bonnet for the SCR relay the type Karl uses has a light to indicate operation is that flashing at the same rate ? I'm wondering if the LB is causing the voltage to fall from the alternator, but that would suggest that the LB is dead/dying - after 4 years that's quite possible but it isn't normally associated with the charge lamp doing odd flashing.
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Eratosthenes
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Re: Flashing charge light

Post by Eratosthenes » Tue Jun 15, 2021 10:43 am

Geoff,

The dash charge light appears to be full intensity, as do other
other dash lights.
When I noticed it flashing last night I returned home, about half an hour driving
and as far as the engine performed, that seemed normal.
With regards to the relay under the bonnet, with engine running and in the shade
the led is only just visible. It is not flashing, and previously when I have noticed it from memory
it seemed brighter.
I don't know if it is significant, probably over the last 3 years the LB has virtually had no use at all.
Only the cabin lights and radio are connected to it. The cabin lights are led and I can't remember
the last time they were used and the same with the radio. Circumstances change and we now use a caravan.
I always mean to connect a qrp hf transceiver but have never got round to it.
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Re: Flashing charge light

Post by g8dhe » Tue Jun 15, 2021 1:34 pm

I think you may have to have a probe around with a meter to find out what is going on then!
The alternator when it isn't generating sends out the earth to the dashboard, it does feed via diodes both the Charge Lamp and the Sediment Lamp (for self-test purposes as the sediment sensor is a simple reed switch) so there really shouldn't be any reason for a regular flashing .....

The only Flashing signal is normally controlled by the ECU to either the Glowplug or Hold light(s) depending on engine type to indicate an ECU reported problem.
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Re: Flashing charge light

Post by Katka » Tue Jun 15, 2021 6:40 pm

Might it be worth disconnecting the LB system and returning it to 'normal' setup, so it can be eliminated from the equation, or confirmed as a factor?
Our scr from Karl failed after about 3 years, but didn't have the symptoms you are describing - just a flat LB
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Re: Flashing charge light

Post by Eratosthenes » Wed Jun 16, 2021 1:33 pm

Thanks for both posts.

We left the Bongo at home and did 2 trips in the wifes car to get away as originally planned.

After talking with Karl and the your advice, when I get home I will be isolating the SCR and take it from there.
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Re: Flashing charge light

Post by Eratosthenes » Sun Jun 20, 2021 8:31 pm

I managed to get back earlier today to work on the electrics and did the following:-

Isolated the split charge relay by removing the fuse - no change
removed the swap loom and replaced with the original fuses - no change
removed the extra accessories I had fitted, (The TM4 - Twin Sensor, Low coolant alarm and Clock) - flashing stopped
new connections for the TM4 and low coolant alarm - no flashing
The clock will be rewired tomorrow hopefully to see how that affects things

all connections seemed ok when taking apart and inspecting them

However I will run it for a couple of days and if all is well will solder and heat shrink new connections
(The original connections I had made were crimped bullet connectors - maybe this has been the problem - I did put a meter at each end
of the connection, but that was about 4 years or so ago).
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