BJ-42 electrical system woes, please help

[bagh33ra]

Sorry in advance for this being so long, but I want to give as much information as possible to let everyone know what has transpired to get me to this point. Thanks in advance to anyone who can help.

Truck Spec:

1982 BJ-42, RHD, NZ origin. 3B. 12v electrical, 2 batteries in parallel. Alternator mated with vacuum pump, externally voltage regulated.

A while back I came out one morning to start the truck and had dead batteries. I noticed at that point 1 really badly corroded fusable link, which I replaced. I also noticed that the batteries were mismatched and of unknown age. (Stickers missing or illegible)

Also, I want to point out that there is a great deal of DPO wiring in this truck. Thus far I have finished removing all of the AC components as well as the 3 CB radios that were in it. Both of those systems were connected to the Lighter outlet fuse. The lighter itself was connected direct to one of the batteries with an in-line fuse. That has been corrected.

There was also a green light next to that point, but only the ground side of the light was connected. It was T-connected to a portion of stripped wire, no tape around it, connected to what should have been the ground for the lighter outlet.

Anyway, back to the timeline.

Replaced batteries. Continued to have a charging system issue. Took the truck to my friend’s shop and had him run an alternator test. Failed.

Spent a few weeks looking for an alternator (there was a thread about that) and eventually decided to take the alternator in for a rebuild. Got it back within a couple of days, and reinstalled it. Outwardly it appeared as if they did a tremendous job.

Reinstalled the alternator and carefully connected the wires. I’ll try to draw a diagram of some weird DPO wiring relating to the alternator. Basically there is the stock wire connected to the post, and a second that connects to the battery through a relay. Part of the relay wire comes through the firewall and is jammed into one plug of a 3 plug connector near the driver’s pedals. (ugh).

When I connected the first negative battery terminal, there was some sparking at the terminal. I shrugged and connected it anyway (my mistake). Immediately there was a small shower of sparks from some of the leads from the positive terminal into the harness.

Found the wire which was expected to be the source of that shower. It was heavily corroded on the inside, you could pull on it and it would stretch like there was no wire inside. Replaced that.

Now I have no lights, no glow, no starter, no nothing.

At this point I have examined several relays all of which seem to be fine, but I am going to test them again. Each relay (glow plug, a small round one behind the silver dash panel, and a second one next to the glow plug relay) has continuity where it should, and clicks over correctly when voltage is applied directly.

I don’t think I have tested the EDIC relay, unless that is the unmarked one which is next to the glow plug relay. Note that these relays have been moved from their stock positions by the PO.

This is when I found all the AC, CB, and cig lighter wiring madness I mentioned above. Still no love.

So, where it stands now is that I have voltage coming in to the ignition switch, but it drops to 0 when the key is turned to any position, OR when the brake pedal is pressed (?)

Continuity between the ignition switch points seems correct when checked. And last night I tried disconnecting the ignition, and jumping the contacts to get power out to other systems. While I did not measure voltage while that was happening, I got no lights, no start, no acc stuff either.

I have been trickle-charging the batteries in-between debugging sessions as well, although I am uncertain if there was enough amps in them last night to be effective.

Any and all ideas and assistance are welcome, including a source for an entire new harness if that is necessary. Tomorrow I am hoping to re-wire the tail lights as there is some DPO hack wiring back there which may be why depressing the brake pedal drops the voltage. That is, as long as the weather cooperates. Not having a garage is rough!

Again, my apologies for the long post.

[bigboss]

hey bagh i want to know if you ever got this sorted hate to see a man in trouble when i might have the ansers

[lostmarbles]

Perhaps it's one of my compatriots taking revenge on you for stealing one of our cruisers?

Seriously though. I feel kinda responsible since I'm from NZ too!

Unfortunately I doubt anyone can help - Except possibly to give suggestions about fitting a new wiring harness. From what you say, it appears the PO - (I'm getting to learn all these MUD abbreviations) - has done way too much damage. (Is DPO "dipstick previous owner"?)

Good luck with fixing the mess.

The only thing that should draw any current on my BJ40 (when everything is switched off) is the antitheft system on the radio. So if I were to see any sparks when connecting the battery up - I'd immediately knowing something was likely to be seriously wrong.

Also I often check my alternator just by putting a cheap voltmeter across the battery. Without the engine running the battery voltage should be between 12.6V and 13.6V. When the engine is running, the alternator should boost this to between 14.4V and 14.7V. (The higher voltage being necessary to charge the battery.) A better test (which I also do) is to check the actual charging current but that is more complex.

If a battery is discharged - it will read only around 11.6V (or less) with the engine off. (But if the voltage is higher/good - It DOESN'T necessarily mean the battery is OK/fully-charged.)

To check the battery properly, I have one of those old devices that you push down onto the terminals and it reads the battery voltage UNDER LOAD (ie. While there is a big current being drawn from it.)

Again ---- Good luck.

[bagh33ra]

Originally Posted by bigboss

hey bagh i want to know if you ever got this sorted hate to see a man in trouble when i might have the ansers

Welcome aboard BigBoss. Nope, not sorted yet. I finally got around to writing the post yesterday. Thought I would drop in to see if there was any advice before I started today's run. Unfortunately this is all happening while I am moving, so going around to look at places is cutting my work time drastically.

Lost,

Sorry about being one of the guys who wound up with a cruiser hijacked from NZ, but I just had to have one! Batteries were in the low range of voltage, but I have no way to test them with the alternator running.

Just checked them after pulling off the charger. one i at 12.8 and another reads 14.0x (it was fluctuating a little).

[lostmarbles]

Originally Posted by bagh33ra

Lost,
Sorry about being one of the guys who wound up with a cruiser hijacked from NZ, but I just had to have one! Batteries were in the low range of voltage, but I have no way to test them with the alternator running.

Just checked them after pulling off the charger. one i at 12.8 and another reads 14.0x (it was fluctuating a little).

My info says a 12V battery should read 13.6V after driving/charging and this then drops down to 12.6V after a "settling period". So I think your voltages after pulling off the charger are really inconclusive. (It is not possible for a "battery fault" to cause it to have excessive voltage - As far as I understand.)
Anyway- your problems are obviously more to do with wiring so I'll butt out now.
Cheers

[bagh33ra]

Yeah, I don't believe that the batteries are at fault during my testing.

I did finally locate the EDIC relay (Labeled Fuel Control Relay) but am uncertain as to how to test it's operation.

The connector going to it did exhibit a level of copper corrosion, which has been subsequently cleaned from both sides.

I also finally determined how the trailer plug (7pin) wiring is impacting the problems. Again, bare-wire connections, bare-solder connections and a T connection to a stripped section of the stock harness. I tried to take some pictures of that mess, but none of them came out very well. My opinion is that bare-wire connections are a bad idea, so I am repairing that section as well. It may be pertinent to my "no power" condition as when the brake pedal is depressed voltage at the ignition drops to 0.

Also, I believe the glow plug relay to be faulty as well. When either using the ignition key switch for glow, or jumping voltage in to the glow wire at the ignition plug, voltage arrives at the relay as expected. Voltage does not come to the actual glow plugs. When direct connection the voltage in to the relay to the out to the glow I get voltage at the glow plugs. I attempted using a standard 30A relay as temporary replacement to see if I got voltage at the plugs, but I might have misconnected as that did not result in voltage at the plugs.

I also go inconclusive readings at the relay (standard 30A one) output point as well. I am going to re-perform that test and take more careful notes.

*sigh*

Frustrating. Anyway, I took down all the numbers for the 4 relays that appear to be stock to the truck. Glow, EDIC, unlabeled one that appears similar to the starter relays I have seen pictured, and a 4th small round one which may or may not be a flasher relay. Going to attempt to source those, even if only the glow relay is bad, I want the spares for others on hand.

[lostmarbles]

Hi again. Your wiring problems are so complex that it is difficult for me to comment on them. Besides my vehicle is different to yours. It's older with a B engine instead of the 3B. So ---Much of my wiring and components are different.

It looks to me like you're tackling your problems sensibly though. But I found trying to stock spares (items you don't immediately need) is too costly/difficult for our OLD vehicles. And since I am a "reformed hoarder" it "goes against the grain" in that respect now too.

When I bought my BJ40 back in 1981, one of the first jobs I did was inspecting all the after-market wiring work. Like for the trailer socket, radio/cassette, air conditioning etc. I redid properly all the twisted "barewire" connections and the ones than use those horrible devices that gain electrical access to a wire simply by biting through its insulation.
One method I used (where I wanted a permanent connection that never needed to be disconnected/reconnected) was to slip "heat-shrink sleeving over the wires I was joining, twist the copper strands (clean shiny copper) together tightly, solder the tightly wound copper strands, slip the heat shrink sleeving back over the entire joint, fill that sleeve with NEUTRAL CURE silicon sealant, then use a hair drier (without telling the wife) to shrink it (which squeezes out surplus silicone) to leave a watertight insulated permanent troublefree joint.

[bagh33ra]

Hmm. Nice method for new connections, I'll have to try some of that as I re-add things to the system.

At this point I am removing all the aftermarket/PO wiring wherever possible and minimizing the places that I have to look for problems. At the same time this is resolving a lot of potential problems.

Regarding spares, I'd rather not stock too many - but some things I would like to have around to avoid the wait time for getting them shipped. Even from Canada it takes a while, and if I have to source stuff from OZ that is unique to the RHD versions of the truck.. man I don't even want to think about that one. Mostly I want consumables around (filters mainly in that category) and the relay thing is mostly paranoia on my part now. I'd hate to be stuck a few hundred miles from home for want of an EDIC relay.

I'll keep posting up what happens with the debugging, and keep trying to get some good pics to show folks if they would be at all helpful. I *will* fix it, and I will definitely learn a lot in the process.

On the bright side, I'm going to wind up VERY familiar with the wiring on this truck when all is said and done.

[bagh33ra]

A bump and a bit of a progress report.

First, all pics are going to wind up here with some description in the caption and comment field. Turns out that board software doesn't embed these very well into posts, (tested on a different board so maybe will try this one again) I'll just drop links to pics that are pertinent.

So, here's the album. Cover pic is the truck as delivered in July:

http://picasaweb.google.com/bagh33ra...iserElectrical

Nothing much exciting in there at the moment, just an example of some of the wiring work I am following behind. Sorry the one pic is kinda fuzzy. In fact, I imagine that this is all very rudimentary to most of you. For me, well, still learning this, so yeah. Useful info for other newbies like myself, maybe?

So, I'll put up some of what's been done, and try to clearly mark any theories or questions so folks don't have to read the whole thing unless they want to. If there are other methods I should be using to find the problem, or if the conclusions I am making go against any general electronics theory - please let me know.

What's in the Pics?
That basically represents the tail light wiring, and the hack-job installation of the trailer electrical socket. I've essentially removed it from the system, and semi-sealed up the connections (and the ones not connected as there is no socket).

Prior to that, voltage coming into the ignition switch would drop to 0 (from 12.7+) when the brake pedal was pressed. Now that the hack wiring is out, that no longer happens. Yay!

If folks are interested I can post a detail about how I determined which one was what, but that seems excessive as it is now fixed.

Here is where things now stand:

Ignition key switch continuity tests:

From Voltage in, turn key to a given position, test continuity (meaning the switch completes the circuit as expected):

Key to Glow, cont b/n Glow And In. None at any other point.
Key to Acc, cont b/n Acc and In. None at any other point.
Key to On, Cont b/n Acc and In, also b/n On and In. None elsewhere.
Key to Start, Cont b/n On and In, also b/n Start and In. None elsewhere.

Measurements were consistent at the solder points on the ignition switch, and at the plug connector at the base of the steering column. Leaving the socket disconnected, isolating the ignition switch and couple feet of cable leading to socket, I measured for continuity to ground for that length at each point. Found none.

Hypothesis:

Ignition switch, including wires up to first plug at steering column are fine. No short there.

Finding Voltage

Measured at ignition solder points, Base around 12.7v

Key to Glow: drops to 0
Key to Acc: stays constant
Key On: drops to 0
Key to Start: drops to 0

Brake Pedal Depressed: now fixed and stays constant after work described above.

Question:

I found the inputs of the glow plug relay and that they had continuity between the plug at the ignition switch and the plug on the relay. There was 1 in from the Glow key position. And another from the Start key position. This seems to make sense to me, if the glow plugs receive voltage when attempting to start the engine. Can anyone confirm that it works that way?

There is voltage coming in to the glow plug relay from the battery. There is 12.7ish coming into the signal when the key is switched to Glow. I need to remeasure to be certain, but I believe no voltage comes in from the Start line to the GPR when key is switched to Start.

I suspect the GPR relay to be bad, although I do not thing it is my only problem at the moment.

Again. No lights, No glow, No starter activity. More measurements and another bump coming soon. Oh, and maybe some more pics too.

[lostmarbles]

Hi David. Be nice if others with experience of your 3B could add their 2 cents worth.
Nice pix. I've always liked the look of the mudguard-mounted Donaldson air cleaners. Some Aussis tend to go for the "Kenworth truck look" but sometimes they go overboard with their massive bull-bar designs in search of this goal. (Not yours though.) Yours looks magnificent except for the scary wiring.
I like your thorough investigation techniques but I don't follow this "voltage goes to zero" business.
My understanding of "earth-shorts" (wires short-circiting to ground) is that they should either result in blown fuses or burnt wiring. (Nothing else.) If instead, you "lose supply voltage" whenever the short occurs - That would indicate to me that there is a loose/corroded (whatever) connection upstream of that point which is causing the voltage drop. (If this were true, it could well prevent downstream relays from working.) Are you really sure you repaired the fusible link(s) properly?
But I may well be misunderstanding what you're saying.
Cheers
PS. -My B engine shouldn't have power to the glow plugs when the key is in "start" but I think your 3B is different so it is probably alright for you.

[bagh33ra]

Originally Posted by lostmarbles

Hi David. Be nice if others with experience of your 3B could add their 2 cents worth.
Nice pix. I've always liked the look of the mudguard-mounted Donaldson air cleaners. Some Aussis tend to go for the "Kenworth truck look" but sometimes they go overboard with their massive bull-bar designs in search of this goal. (Not yours though.) Yours looks magnificent except for the scary wiring.
I like your thorough investigation techniques but I don't follow this "voltage goes to zero" business.
My understanding of "earth-shorts" (wires short-circiting to ground) is that they should either result in blown fuses or burnt wiring. (Nothing else.) If instead, you "lose supply voltage" whenever the short occurs - That would indicate to me that there is a loose/corroded (whatever) connection upstream of that point which is causing the voltage drop. (If this were true, it could well prevent downstream relays from working.) Are you really sure you repaired the fusible link(s) properly?

Actually this is very close to what was happening. Sorry I couldn't post a follow up, but good news, I finally figured it out! Actually figured it out just a couple days after my last post, but had to find an apartment and get moved in the interim. Leaving tomorrow for Jawbone Canyon, (Mojave Desert) so also busy getting prepped for that.

Thanks for the comments Lost - I actually haven't decided if I am going to keep the air cleaner or not. It definitely adds character and gets a lot of comments, same with the bull bar. Those types of decisions are for later though.

Anyway, back to the story. After reading your post I realized that I was thinking about this all backwards. I started looking at where the harness came off the battery and through the firewall. I discovered that there was a single line from the battery going to what were probably a set of stock connectors. The result was 1 wire splitting into 5. Using continuity I found where they were on the connectors just on the cab side of the firewall:

1 pair goes to the GPR and the ignition, the other 3 are smaller gauge (16 maybe?) terminate at various points of a 17 pin connector. Of these, 2 were not getting power, and a 3rd was intermittent. Tested the new fuses in the fuse links that were in line to 2 of these, and they were fine. Started testing for power backwards towards the battery at each spot with a connector and finally hit pay-dirt!



The culprit is posted in the album.

http://picasaweb.google.com/bagh33ra...iserElectrical

Basically you have it nailed. The upstream failures at that connector were causing the behavior I was measuring at the ignition. I replaced the single wire into 5 with 2 leads from the side post of the battery. One goes to the two heavies, and the other goes to the 3 smaller ones.

What's the moral of this story? If there is no voltage, start at the source then measure for voltage at each junction outwards until the point of failure is found. Use continuity tests to identify individual wire segments along the way and keep testing. Not really realizing it, I was testing things in the opposite direction that I should have been.

In my case it was right next to the friggin battery, which would have saved me a lot of time and front panel disassembly.

There are still some issues to be ironed out, I want to reconnect those flood lights, and setup the trailer wiring properly. But we're back up and running. It's certainly a lot less daunting now, and I am going to develop a solid plan for how the rest of the wiring work is going to be laid out.

[lostmarbles]

Originally Posted by bagh33ra

.......but good news, I finally figured it out!.......

That's great David. You've proven that with "thirst for knowledge" and "do it yourself attitude" you'll usually "win out" in the end. And as a bonus, the whole experience can be quite fun!