Electrical issues

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lizdigs
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Electrical issues

Post by lizdigs » Sun Jan 02, 2022 4:07 pm

Hi, I’ve been having electrical issues for a while now, originally started as a speedo fault (it completely died), the garage attempted a fix but that resulted in the speedo and rev meter jumping around whilst driving and the fuel gauge being inaccurate. I returned to the garage and they thought there was perhaps a fault on the circuit board due to an earlier alteration on it and that I’d need to replace it at some point but I left it due to lack of funds and the van itself was running ok. Now however the glow-plugs light flashes and the van goes into limp mode (or sometimes the hold light flashes).
So I feel like I need to go back to the beginning with the speedo fault - I’ve read that this could be down to a fault if it has a mileage chip (which mine must be as speedo and odometer are both in miles). This would presumably be linked to the alteration to the circuit board too? So, after al lot of waffle, my questions are; how do I access the chip? Is it easy to replace? Where do I get a new one from? Do you think the chip is the answer to all the other woes?? Thanks for reading this long post and any help you are able to offer [-o<
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g8dhe
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Re: Electrical issues

Post by g8dhe » Sun Jan 02, 2022 4:17 pm

The Speedo chip is just a little module with 4 wires connected to the back of the cluster itself and yes they fail on a regular basis!
Speedo_chip.jpg
As I recall Red and Green are power and the Blue and Yellow intercept the original signal from the sensor, to reinstate just put the wire that connects to the Yellow back on the Blue tag location leaving Blue and Yellow out of the circuit completely to test. Different versions of the module will probably use other coloured wires so be aware of locations they connect to and I would suggest taking pictures before and after so you can reconnect easily!
Geoff
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lizdigs
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Re: Electrical issues

Post by lizdigs » Sun Jan 02, 2022 6:08 pm

Thanks Geoff, that’s really helpful. Do you know where I can source a new chip?
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g8dhe
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Re: Electrical issues

Post by g8dhe » Sun Jan 02, 2022 6:45 pm

Geoff
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lizdigs
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Re: Electrical issues

Post by lizdigs » Sun Jan 02, 2022 7:16 pm

Ooh, thank you, not *too* expensive! Think I'll start with the chip and see how I get on, if I can fix all my issues for £25 I'll be very happy :lol:
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g8dhe
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Re: Electrical issues

Post by g8dhe » Sun Jan 02, 2022 10:17 pm

An even cheaper starting point is to check the sensor and give it a clean, it has been known just to be a collection of sticky old oil and swarf that is preventing the right pulses coming thru!

Actually just re-read your symptoms, are BOTH the speedo and revs changing together, or is each randomly flickering ?
The fuel gauge problem may well be the usual earthing problem of the tanks as well, add an extra earthing wire to the fuel tank to the chassis there are existing holes for self tapping screws which can be used to hold terminals in place.
Geoff
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lizdigs
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Re: Electrical issues

Post by lizdigs » Sun Jan 02, 2022 10:52 pm

They’re now both randomly flickering since the garage tried to fix the speedo which had just died completely.
The fuel gauge worked fine (it has been previously earthed to the chassis) too until the speedo fix. So I feel there’s something going on behind the dash I just don’t know what!
Rickster
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Re: Electrical issues

Post by Rickster » Mon Jan 03, 2022 4:10 pm

I have one of them speedo boxes here if it's any use, I changed the dial to MPH and removed the box, the wiring was put back as standard👍
lizdigs
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Re: Electrical issues

Post by lizdigs » Mon Jan 03, 2022 5:13 pm

Hi Rickster, that would be good, thanks. How much are you after for it? Does your odometer now read in km without the chip?
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Re: Electrical issues

Post by Rickster » Wed Jan 05, 2022 6:34 am

Please bear with me, I don't know where I put it at the moment so will take probably a few days of searching, things move around this place at a fast pace.
lizdigs
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Re: Electrical issues

Post by lizdigs » Mon Feb 21, 2022 5:06 pm

Hello, I finally got round to taking a look at the Speedo chip today... the electrical circuit looks a bit of a mess (photos attached) - can anyone see an obvious issue? Could it be worth replacing the chip of should I try to replace the whole circuit (if so, where would I get one from??).
My other big problem is that when driving for any longer than an hour the glow plugs light will flicker and the engine will do a little hiccup and lose power. The glow plug light doesn't stay flashing. Is this likely to be an electrical issue rather than an engine/gear box issue?
Also @Geoff, on one of my previous posts you mentioned earthing point 7 with a diagram attached but I can't zoom in on the picture to check the location - would you be able to re-send please?
Many thanks.. [-o<
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g8dhe
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Re: Electrical issues

Post by g8dhe » Mon Feb 21, 2022 5:32 pm

lizdigs wrote: Mon Feb 21, 2022 5:06 pm My other big problem is that when driving for any longer than an hour the glow plugs light will flicker and the engine will do a little hiccup and lose power. The glow plug light doesn't stay flashing. Is this likely to be an electrical issue rather than an engine/gear box issue?
Also @Geoff, on one of my previous posts you mentioned earthing point 7 with a diagram attached but I can't zoom in on the picture to check the location - would you be able to re-send please?
Many thanks.. [-o<
For flickering lights and little hiccups I would be suspecting battery connections or possibly fuse connectors, I would suggest removing the battery terminals cleaning the posts and connectors and then reconnecting (always start with disconnecting the -ve terminal first and reconnecting it last)!
The location 7 for earth is under the righthand end cap of the dashboard I believe (long time since I looked!), open the drivers door wide and there is a plastic flap that clips in position see here;
Earth point 7.JPG
Geoff
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