Wires in Sacramento area

[68DSU]

You guys are great! thank you.

[dbrick]

Not to step on JT, but you mentioned the shop may have added wires to get it running. that's a red flag for me to 1. Not use that shop to trace your wire, and 2. find out what the added wires are doing.
IMHO, the harbor freight multi meter is a great spare, also great for amp testing, as blowing up a $5.00 meter costs less than fuses for a Fluke. The test light from Harbor freight is a great tool.
In the long run,spending about $25-$50 on a decent low end meter, from Sears or home store, or a used Fluke on Ebay if you have the time to shop is a better bet. Autoranging is a big help.
Sears DT916N or DT931N will get the job done

[JT68]

Yep, nice meters, like most tools, are usually worth the extra funds. In this particular case most of the trouble shooting can be done with just simple diagnostics and/or basic meter.

From tests 1&2 above, we temporarily eliminated the relay which tells us a lot:

If the lights lit when the relay was bypassed,
1) we confirmed the supply and control circuit either works (or doesn't)
2) we confirmed the load (lights) and load circuit works (or doesn't).

If we want to verify the findings:

With the switch "on" there should be +12 (relative to chassis) on the red/yellow wire (meter will verify).

If you apply +12 to the red/black wire both low beams should light. - confirms that entire circuit is intact.

If you apply +12 to the red/white wire both high beams should light. - confirms that entire circuit is intact.

Let us know what you find and that will tell us what to check next. j

[2mAn]

This is written in a way I can understand... I should dedicate some time to this ASAP

[68DSU]

I bought a meter and made the bypass wire but I've been staying inside the last few days. Smoke from the fire north of here is pretty thick and is hitting "unhealthy for everybody" levels. This isn't a complaint, just a reason why I haven't got back with results. When I smell the burned wood with a touch of plastic in the air, I know it is someone else's whole life going up in smoke. Again, no complaints from here.
If there is anyone here from the Paradise area who needs help, I'm just sitting around waiting.

[greydog]

Those fires are just awful.
Glad you're ok Rick.
Last year some of the people here were involved with the Clear Lake area fires but luckily no on was hurt.
I did some firefighting as a young man but it was here in the Pacific Northwest. We lost a cat I was driving and a few other pcs of equipment but it was never in a city and no one got seriously hurt.
These California fires just seem to be getting more and more lethal.
Again, I'm glad you're ok.
Dan

[Linda]

I concur with dbrick about no worries blowing up a HF meter. I have 4-5 of them, since I can get them free with ANY purchase, LOL, and I cross check them with each other. Plus in the beginning I was using the wrong settings and broke a few I might have to graduate to something better though one day....
Linda

[68DSU]

Those fires are just awful.
Glad you're ok Rick.
Last year some of the people here were involved with the Clear Lake area fires but luckily no on was hurt.
I did some firefighting as a young man but it was here in the Pacific Northwest. We lost a cat I was driving and a few other pcs of equipment but it was never in a city and no one got seriously hurt.
These California fires just seem to be getting more and more lethal.
Again, I'm glad you're ok.
Dan

We were never in any danger here, it has just been hard to breath. Burning eyes and a little tightness in the chest but again, better than facing flames.
I'll be back at the car tomorrow.

[JT68]

No worries. Glad you are safe out there! Way beyond terrible.

I'll continue on with the next group of tests just to make the thread complete.

So if you have 12V on the red/yellow when the switch is on, and both the Hi/lo circuits work when jumpered, you most likely need a HL relay. Easy enough.



Let's assume there is NOT +12V on the red/yellow when the switch is pulled all the way. That means the problem is between the battery, switch, and the red/yellow relay wire. The relay may actually be OK, but we need to get it powered up.

Since the red/yellow is controlled by the switch, the next basic test is:

When you pull the light switch ON to the first position and second, do you have front and/or rear running lights?
On my 68 all 4 rear running lights and the two fronts are lit in both positions. I think this should be correct.

a) If ANY of the running lights work, that means the switch is getting 12V.
So....you either have a bad switch (failing to energize the red/yellow) or the red/yellow line is an "open circuit" - not connected to the switch.

The engine harness connects to the dash harness with several connectors inside the firewall right next to the clutch master cylinder- a connection may have failed there or be disconnected. --other than that one connection under the dash, and the actual connector at the switch, the red/yellow is a straight connection to the switch. You need to inspect those connections.

b) If NONE of the running lights work, the switch is not getting 12V or the switch is totally defunct-possible but not that likely. Make sure the switch connector is fully connected, and nothing looks burned or melted. If all looks good, the most likely culprit is the fuse box, but there are some other possibilities. I'll post those tests next.

Hope this helps! jt

[2mAn]

I had a few minutes to try the jumper wire and got zero lights... which sucks because it might be dark-ish on my way home tomorrow

[Curtis]

The fuse box is well known to be a problem. Check first that you have power on both sides of the fuse with the large red wire.

[2mAn]

Pull the fuse, test light from one side to the other? ... remember Im a dunce so if this seems obvious, it really isnt to me

[Curtis]

First with the fuse in I would check for 12v on both sides. if you don't then pull the fuse and check it. The rivets are known to come loose and be a problem. Check the fuse clips and make sure they aren't loose.

[JT68]

I had a few minutes to try the jumper wire and got zero lights... which sucks because it might be dark-ish on my way home tomorrow

Ok, in this particular case, it sounds like the relay is not getting powered up.

How about the running lights? Any alive or all dead?

side note: If you need lights for a true emergency, you can make an long emergency jumper from +12 (battery) to the red/white wire at the relay. just don't let it touch chassis. (You could put a 20A fuse in the jumper, right at the battery to be extra safe). This would not give you running lights or brake lights, so not very safe.

- For Simon specifically, You did starter work recently I think. Did your lights work before the starter swap? If so, there is a group of connectors between the air filter and the firewall, below the master cylinders, anything disconnected there? Easy to knock those loose while working on the starter//



Let's return to a systematic approach though:

If no running lights AND no headlights, either your switch is bad, disconnected, or the light power circuit has failed, we'll step through those next:

As Curtis mentioned, a convenient place to check for supply voltage is the fuse box. Use your meter, set to measure DC Volts for this test.
If you are unsure off your meter skills, measure a couple batteries..1.5V,9V, 12V etc.

all this testing is '68 specific:

Ground the black test lead (any bare chassis metal-emergency brake handle is fine) and touch the red test lead (one at a time) to each metal fuse contact on the second fuse from the top in the fuse box. Both sides should show 12V, but probably do not.

If only the left side has power, your fuse box/connections/fuse has issues. You have found the problem.
(corroded or burned terminal, bad, blown or melted fuse, poor connection etc.)

If both sides are dead - zero V- the problem is more likely out at the starter connection, so you would need to trace that path. The entire light supply (supply to #2 fuse) is via the large white wire (left side of #2 fuse) that runs directly to the starter battery cable connection. It does goes through a couple connectors. **Use caution testing this wire- it should be +12 always if the battery is connected - it is not fused- a direct connection to the +12 battery cable**It connects ultimately to the little harness that connects to the starter and to the battery cable.

Let us know what you find. If you test with the meter successfully, you are zeroing in on the problem- there isn't much left.

Remember, for safety, if the engine/alternator isn't running, if you simply disconnect either battery cable, everything is powered down and very safe.

j

[68DSU]

I'm way back on basics. I'm checking and cleaning all the connections in the circuit. They looked pretty grim.