Low Voltage - Dash illumination, Clock & Radio power

jimmyt

New Member
I am in australia
May 11, 2014
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0
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Hi All

Vehicle 1993 80 Series; HZJ80

My dash illumination, clock and radio are not works so I set about looking for the issue. I am not the best on electrical issues but understand the basics, I think…! Can anyone help.

Ignition voltage a healthy +12v
Constant Battery Voltage is a dismal 2.6 volts between the Radio L-Y (Blue+Yellow) wire and the battery –ve terminal . I assume I have a some corrosion somewhere that is causing a large resistance.

FYI, I connected a test wire to the battery –ve terminal to eliminate earth issues.

L-Y power is coming from the ‘DOME’ fuse in the Relay Box (R/B No.2) on top of the LH wheel arch. Voltage is good at this point and also good at the 1[SUP]st[/SUP] connector plug [EA1] just behind R/B No. 2. I have checked all of the wire harness connectors for corrosion, pulled them apart and cleaned. There was a lot of red dust in the LH foot-well connectors (from the Australian Outback) so I knocked & blew it out.

The L-Y wire seems to split to many areas of the vehicle and does not sow 12v at all of the plugs. Some of these plugs are not in use. I have disconnected the harness at the rear of the vehicle to eliminate potential shorting issues there however I have not manage to find the issue yet and I still get 2.6v at the radio L-Y wire.
I found a L-Y Wire in a connector in the LH foot-well, there was a good 12v here but if I measured the resistance from here to the Radio L-Y wire there was 150Ohms of resistance. I’m assuming this could be where my issues is.? Also if I measure the voltage across these two points I get 10v…..! This seems a bit odd as they are the same wire…. unless it means I have a short somewhere between them.

The Electrical Wire Routing diagram shows a Junction Connector (J3) which I have not manage to locate, does anyone know what it would look like – are there plastic connectors or just a place in the wrapped loom where the wire splits…? The Manual image shows it at the top of the dash on a LHD but mine is a RHD, I’d assume it would be the same…?!

If anyone has any pointers I be grateful.
Also, looks like previous owner had beached it at some points. Some areas of the vehicle were pretty messy. I have replace all major earth straps to chassis & engine.

Regards
James

1.JPG 2.JPG 3.JPG 4.JPG
 

Towpack

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I am in england
Oct 4, 2011
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It's not uncommon for wires of the same colour to be spliced (usually soldered) and taped up in the main body of the loom although, looking at the wiring diagram, there doesn't appear to be such a joint between the power feed from the dome fuse to connector J3. Assuming the LY wire is continuous you obviously have a HR connection somewhere. Some of the electrics behind the dashboard are susceptible to leaks from the windscreen if/when they happen. Have you noticed any water ingress round that area?
 

jimmyt

New Member
I am in australia
May 11, 2014
14
0
6
Towpack, thanks for the response. I have not noticed any windscreen leaks however it has been submerged (previous owner) in water at some point so it sounds like I may need to get behind the dash to see if these has been any internal loom corrosion. May be good to get it all out anyway.....

Thanks
James
 

jimmyt

New Member
I am in australia
May 11, 2014
14
0
6
Found it...and fixed it !
Managed to isolate the area of concern and eventually found a heavily corroded wire inside loom engine bay just before bulkhead...
Now to re wrap loom and reassemble the dash....
Hope there are no more....
 
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jimmyt

New Member
I am in australia
May 11, 2014
14
0
6
All

For records folks; the corroded wire was in this location buried about 30mm from the bulkhead. See Blue & Yellow wire in image fixed with heat shrink now protecting.

James

CorrodedWire.JPG
 

StarCruiser

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I am in uk
Oct 7, 2014
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Yes, well done indeed for finding that. I have often cursed the practice of splicing looms at the factory without it being obvious or at a connector or such. Once you know they do it, it's not so bad but it does make finding this sort of thing a challenge.
 
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