Not making sense

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Joined
Jan 2, 2005
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278
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CouleeDamWA, BoiseID
Ok I’ve three wire right next to try battery. The thicker ones at Black and then White as I hope you can see in your photo. The red one is smaller. I hooked them up how I see the wiring diagram. The black one does absolutely nothing when placed in the positive end of the battery. But the white one starts opening and closing a relay. The red one does the same.

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The fusible links are given in the wiring diagram you posted. Colorcodes R W B match. But this not only applies to the fusible links themselves, but also to the cables that continue on. The fusible links are rather short pieces of wire (~5 inch) and usually connect by a bolted connector to the harness.
I believe you are looking at the harness here, with the connector and actual fusable links missing.
Make sure to put fuses of some sort here!!

The black cable doing nothing (without further action like turning key or a switch) appears normal to me.
A relay however kicking in (it clicks, I assume) indeed makes little sense.
Can you identify where the relay exactly is located and what it does?
The parts diagramm have a page that show location of the relays, switches and stuff..
Good Luck Ralf
 
Is your battery already connected at all?
If so, what's on the positive terminal right now?
From factory, there should only be those 3 fusible links into the harness and one or two big cables to the starter.
 
This is how it looks at my truck.
Same R W B. Black goes to a bolted connector, which goes to a dark blue fusible link and to the battery.
Red and white to a green plug, which I believe is a coil to cancel electric noise (?).
It also ends in two fusible links to the battery.
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(The red cables in the woven plastic protectors are non-factory additions.)
 
For mine both battery cable grounds are bolted to the engine block. He had both positive cabled attached to one another. It is a bit confusing with that part of the wiring.

Black= 8vdc
The white and red wire both are around 12.6vdc

The white one causes the control valve to move back and forth really fast and under the dash on the passenger side (US) it makes a solenoid go medium speed.
We’re as the red wire one has a solenoid in the same area but makes the control valve arm go really slow but that solenoid sounds different and goes faster. There is no green connector.

I will pull the battery again and this time I will look at each connector and see what it goes to. Then report back.
 
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For mine both battery cable grounds are bolted to the engine block. He had both positive cabled attached to one another.
If I get this right, you have two 12V batteries in your 12V truck (?), which are wired 'parallel' to double capacity. Interesting.

I had a look at the wiring diagram.
Note: For 3B diesel, page 6 of the diagram is applicable.
RED and WHITE join line "A" in the p6 diagram and feed into the Ignition Switch.
"A" line also feeds the load circuit of the Ignition main relay (becomes"F" when relay (ignition) is engaged).
White also feeds the load circuit of the starter relay.
White and red (as joined anyway) also feed the load circuit of the EDIC (you call it control arm).
The red cable is thin, so without white cable in parallel, this means less power, causing things to move slower.
All in all we have two flickering relays: EDIC and the relay/solenoid under the dash which I bet is the Ignition main relay.
Neither of them should move at all without Ignition switch on, so check what the condition of that is.
A relay may flicker, if the load circuit has a very high load, causing the overall system voltage to drop, which causes the coil circuit to collaps and disengage the relay, which cuts off the load, which causes the overall system voltage to recover, which causes the coil circuit to engage the relay again, which has the high load again... there you go: Flicker
The high load could be caused by the glow system.

BLACK is line "B", which is 'permanent hot' as it bypasses the Ignition Switch.
It has the glow system on it. As discussed in the other thread, your glow system is off factory standard and probably has a manual switch on it.
Your overall battery voltage apparently is 12.6VDC. But on BLACK you only read 8 VDC. This indicates a load being applied, which causes voltage drop.
Possibly your glowing system is on? But also could be something else. Look for it!

I think, you tested RED and WHITE individually, without BLACK on? (And probably all without fuses, as the fusible links are missing on you).
I guess, the system got all power from the little WHITE or RED, which is insufficient, and caused the system voltage collapse and thus the flicker. You were probably close to cook your harness!!

Suggestion:
- Get a 20Amp fuse and wire it to battery positive. Have all experimental connections go over that fuse only!!!
(For the permanent install you must (!) either get the fusible links back installed , or put respective fuses of same rating)
- Temporarly disconnect the glow rail.
- Make sure Ignition switch is off.
Put on BLACK first. Shouldn't do anything.
Put on WHITE and RED together.
See what it does then. Normally it shouldn't do anything, too.

Up and until here.
Please report the result.
When all is safely connected and nothing fancy happens any more, we can discuss the steps to go over the system functions.
Brakelights door interior lights and horn will be the first to check (they usually work even with Ignition off).
The various positions of the Ignition switch next (with glow system dissbled): Check applications per position (e.g cig lighter on pos1, dash gauges on pos2 ...
Glow and start will be the very last to attempt!!
Good Luck Ralf
 
I have the basic FSM that covers most US and CAN models. So nothing specific to this engine.
Also the cables for both batteries are not in series. These are parallel. Both negatives are bolted to the engine block. I mean maybe my brain as gone lame.

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And I don’t think this goes to anything… can I cut it off?

View attachment 3101794
Don't cut it. It's clean inside and looks like it had been connected. We'll see. Probably something doesn't instantaneously work, but you can target that then.
There will be connectors not to be connected at all, though. The harness is universal and has connectors for applications which are not fitted on your vehicle at all. The 2nd pic looks like this.

I'm rather worried on that B-R loose end and the birds nest in the background ...
 
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Some suggestions to enable us to better help you:
- Post some overview pics of the full engine bay.
- Give us some background: Why is that harness that badly cut? Is it original to the vehicle or do you put it as a replacement? Are you only reconnecting the engine bay, or the entire vehicle?
- When posting pics of connectors etc: Post a pic of the item (like you do) and additionally a pic where the item is located in the engine bay or on the vehicle. Right now it's hard to locate.

Suggestions on the approach:
Put a fuse next to battery positive, allways.
- Are you clear on your vehicle main voltage? 12V or 24V? You say it's a LJ (coil springs). LJ is often 12V. But it is 3B, which are often 24V.
Look at the rating of the alternator or the wiper motor or the voltage-/charging regulator. They should bear an indication.
- Don't open up too many building sites in parallel. First clear any open ends on the harness. At least insulate them!
Then check ground!
Then go over main connectors like dash, relays, sub-harnesses, starter, alternator, Edic... Go systematically by application (across the sequence given on top of the wiring diagrams) and find the connectors, not vice versa. As said: Probably an application doesn't instantly work, but neither that nor a loose connector does instant harm. Go one by one
- When most the stuff is connected, do the battery connections as suggested in my post.
Good Luck Ralf
 
Ok I got most of the wiring done. But even with the fuse didn’t work. It still has the same issue. But on a good note that button to turn glow plugs works and it turns over. A few Idiot lights come on.
 
Also the cables for both batteries are not in series. These are parallel. Both negatives are bolted to the engine block. I mean maybe my brain as gone lame.
The diagrams are tricky to read as they usually cover multiple models, engines and regions. The battery wiring shows: Serial for 24V, and bypassing the 2nd bat (B-Y 12V from negative terminal) for 12V (which renders the 2nd bat non-existing on 12V models).

For mine both battery cable grounds are bolted to the engine block. He had both positive cabled attached to one another. It is a bit confusing with that part of the wiring.
This clearly describes two batteries in parallel, which gives 12V (which matches your meter reading, too). Probably not factory, but rather put for extra capacity to crank over the big 3B with 12V only. (There is a reason why most 3B applications are 24V).

Negative to engine block is not common, though. Negative should go to frame (big) and body (smaller), with multiple additonal big ground wires frame to engine, starter, tranny and other stuff. I can look at my rig later and tell details then.

Please note: I have a BJ73 3B 1985 EU spec. Much is similar or even common, but it is a different rig. I also look at a different FSM.
You may share your FSM here, so we are all on the same page (literally).
Cheers Ralf
 

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