No Red/Yellow warning lights, charging. Stumped!

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Ahead
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No Red/Yellow warning lights, charging. Stumped!

Post by Ahead » Tue Nov 16, 2021 1:06 pm

Problem: no ‘red or yellow’ warning lights when starting Bongo ie no handbrake, no oil light, no glow plug, charge or roof light. I do have main headlight beam warning, indicators and heated rear window warning lights working as expected. Van starts and runs but no charge output coming from the alternator. I don’t know if the two are connected.

What I have tried/conditions: ‘95 Diesel auto. battery is brand new 335 type, fully charged. Terminals tight, battery earth to body clean and tight. All fuses appear ok. All external lights working. The 15a fuse that feeds the dash is good and there is 12v power there with ign on. I have 12v at the thicker of the two wires feeding the alternator but not on the thinner (ign on or off). I think this might be the exciter? Belts fine on alternator and tried jump lead to provide additional earth. Have looked over all obvious plugs/cables. I was working behind the radio around the time this started but don’t think I disturbed anything.

Any help suggestions appreciated. I have scoured the net and found a couple of reports of similar but no outcome solution. Cheers. 🙏🏻

I suspect may be alternator (but no lights beforehand either) I will remove and get tested but wouldn’t expect faulty alternator to knock out most of the dash warning lights?
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g8dhe
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Re: No Red/Yellow warning lights, charging. Stumped!

Post by g8dhe » Tue Nov 16, 2021 2:45 pm

You should get the lights coming on well before the alternator comes into play, the self-test and various indicator lights come on before you get to turning the Ignition to Start! As a minimum the Charge light, Sediment lamp and Handbrake will all come on before you start the engine.
There is only the one power feed via the 15 Amp fuse, all the lights are controlled by being earth switched. This would suggest that you have multiple faults, is there any other back story ? any work carried out recently, recently bought or anything else ?
Geoff
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Ahead
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Re: No Red/Yellow warning lights, charging. Stumped!

Post by Ahead » Tue Nov 16, 2021 4:44 pm

Thanks Geoff. That’s my thoughts too. I’ve just spoken to Burfield Alternators and they said the charge light needs to light to get the alternator going so that would explain why no charge.

Last significant work was new metal coolant hose under driver seat, bit of cill welding, replacement rocker cover gasket and new timing belt but all this was done at the same time by Fred at Discount Trucks (I have complete faith in them) and was back on June this year.

I did replace the potentiometer on the Mason Alarm around the time this problem started but didn’t need to dismantle the dash to do it. I have since removed the mason alarm for the moment to rule it out. I was also behind the radio as the NSF speaker had stopped working. Don’t know what to try next..? I would probably struggle to understand a wiring diagram and I can’t access your site plans without flash, but I wonder if there is a dash earthing issue. 🤔
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g8dhe
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Re: No Red/Yellow warning lights, charging. Stumped!

Post by g8dhe » Tue Nov 16, 2021 5:39 pm

It doesn't seem like a dashboard earthing problem, the Charge lamp (and associated sediment lamp) light when the alternator isn't turning, by a switch inside the alternator which supplies the earth to the lamp. The Handbrake light is the same it provides an earth from the switch at the back of the handbrake by simply letting the wire touch the chassis (earth) connection!
You haven't had to jump start the vehicle recently ? I'm just wondering if the the lamps have blown from an overvoltage or any welding work being carried out ?
Otherwise its a case of pull the dash display out and check the bulbs themselves, too rule that out, then connect an earth to each lamp itself and make sure no damage to the flexible wiring board on the back of the display.
Geoff
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Ahead
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Re: No Red/Yellow warning lights, charging. Stumped!

Post by Ahead » Tue Nov 16, 2021 10:25 pm

Geoff…. You are a Legend!

Bulbs all checked out ok and then I noticed very small bit of damage to one of the copper Pcb lines. MM confirmed a break. I have taped two strand of copper wire to bridge the break and all lights are good on start up. I even have a seat belt warning that wasn’t working before but swapped a bulb for a spare. Thanks 🙏🏻 so much. This has been driving me mad for over a week. Just need to refit the alternator now which I am sure will be fine. I should also thank Kevin at Burghfield Alternator centre for good advice and although I didn’t use him, from reviews in the web, if I ever need a rebuild I’ll use them.

But thanks again Geoff, don’t think I would have solved this for a very long time without your advice 👍
Ahead
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Re: No Red/Yellow warning lights, charging. Stumped!

Post by Ahead » Tue Nov 16, 2021 10:26 pm

I probably ought to check now how best to repair the break.. unless my ‘mod’ should suffice?!
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Re: No Red/Yellow warning lights, charging. Stumped!

Post by g8dhe » Tue Nov 16, 2021 10:42 pm

Best type of repair is Silver Conductive Paint - https://cpc.farnell.com/electrolube/scp ... p/SASCP03B not cheap but it lasts a good time if the lid is kept well tightened!
Geoff
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Ahead
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Re: No Red/Yellow warning lights, charging. Stumped!

Post by Ahead » Tue Nov 16, 2021 11:06 pm

Cheers
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