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Opel Rallier since 1977
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Terminal 31 ohms reading looks OK; that is going to ground, and will be very low. (If you touch your ohmmeter leads together, you will probably see a few tenths of an ohm. To be as accurate as you can with very low ohms readings, that 'leads shorted' reading shoudl be subtracted from your actual measurements.)

The change from infinite to 1.2 ohms on 49A when the blinker stalk is moved to either left or right seems normal.

The reading at +49 is non-zero so that is what you are looking for. (The harness should have been disconnected from the hazard flasher switch when you made this to check for shorts. Then you would read infinite ohms. I am not familiar with you electrical experience so was not that detailed.)

The reading on C seems reasonable and would not change with the indicator; that is essentially the 2 dash indicator lamps resistances in parallel. (Or just 1 in this case, since one does not light up.)

That DNI0841 relay that you tried would not be expected to work. It says right on the diagram, and in your included text, that it is for 24 volts! (And it says so when looked up separately.) It just will not work in a 12 volt system... at all. You need to get the right part.

But your real issue sounds like a bad wire. If it basically worked with the cluster out, then something is getting disconnected when the wires are moved. When the hazard flasher is disengaged (not flashing, i.e., normal driving), then you should have 12 volts at the 49+ terminal when the key is in RUN, either with a blinker engaged or not. The voltage might drop a little bit when either L or R blinker is engaged AND the system is working. The bad/loose/disconnected wire is likely going to be any of the wires from the flashert socket except the one to C.

The fried wire to the alternator stud is concerning.... that may well mean that there WAS a short in the systems... that may re-occur. Keep an eye (and feel for heat) on the ammeter area... these are known problems in many old cars, and occasionally end badly in a fire. Be ready to pull off a battery terminal if you see smoke!
 

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Opel Rallier since 1977
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2,130 Posts
BTW, if not yet explained, the blinker works as follows:
  • 12 v goes to 49+
  • 31 goes to ground
  • The blinker stalk/switch connects either the left or right blinkers to pin 49A. When this happens, then the lowe resistance either set of blinker lights of the blinker does it thing, applying 12 to 49A on and off.
  • C is a 2nd output that operates the L & R dash indicators.
And... if the directional signal bulbs are the wrong bulb number, or any dual filament ones are turned 180 degrees in their sockets, then that can casue the blinker to not flash (due to the wrong bulb resistance being connected to pin 49A when the turn signal switch is engaged on either side). So make sure your bulbs are corrent, and are correclty installed in their sockets.
 

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Discussion Starter #43
Thanks this is super helpful. I can’t believe I ordered a 24v flasher! I saw that on the diagram and didn’t think to question it!

I will get the correct flasher and try again.

Matt


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Discussion Starter #44 (Edited)
Looks like I found the issue. With the info that the flasher plug’s 12v power went to the terminal 49+ (thanks MR) I was able to trace the issue all the way back to a loose connection back at the black plug at the fuse box. I jiggled around there and the right turn started working. I jiggled some more and both started working. Cleaning the indicator lights got both of them working normally. I may struggle to get the dash back in, but I will know where to look if there are more issues.

Both the brake warning switch and the flasher seem to be pretty well stuck into position and will not function.

I tried the turn signals with the flasher switch bypassed and also not bypassed. It did not seem to affect the operation, so I left it wired up.

As an added bonus, my red brake warning light and indicator are now shining bright. I do not think this is indicative of an actual issue, maybe a function of the 50 yr old worn out switch? If it doesn’t shut off I suppose I’ll just pull the bulb.

Thanks everyone for their help on this.

Since this was a long post, I will recap.

Initial problem was fuel gauge and tach bottoming out when gas pedal pressed, and blowing fuses.

This eventually progressed to turn both turn signals dead and the flasher socket fried.

First issue corrected was replacing the flasher base. This issue was fixed then progressed to an issue with the ignition.

Tracing the issue with the ignition led to discovery of issue with fusible links at starter and alternator.

Correction was repairing damaged fusible link from red wire from alternator stud to fuse box and fusible link at starter.

Complication was loose wires from pulling the dash and also likely troubleshooting the perceived issue when the ignition stopped working.

Root cause was me being an idiot and trying to jump the car direct to the starter when I had a really dead battery that fried both fusible link just enough to start the cascade of issues.

Matt


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Opel Rallier since 1977
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2,130 Posts
Good progress!

BTW, the fusible link at the alternator or the starter would not fry just by connecting jumper cables to the big stud on the starter.
  • The heavy current to the dead battery would not typically occur if the battery is reeeealy dead as it initially will not accept much charge.
  • Any heavy current from the jumping source would flow direct to the battery, and not through the fusible links.
  • Perhaps what you are saying is that once the car was jumped and running, you think that the alternator was trying to charge a highly discharged battery with a heavy current, and that burned up the fusible links? The alternator's current limit under a near short-circuit load, through the totla resistance of wring, fuse block terminals, ammeter, etc., is pretty, unclear.
  • Know that fusible links are thermal devices, and as such, will 'age' and harden up[ over time and use and repeated heating. You will find them hardened and brittle regularly in old cars So your fusible links were probalby 'on the edge' of going and something finished them off.
  • I'll try not to go on too much about this, but your hot terminal on the ammeter is cause for concern. It might have been just a loose conneciton... or it might be something on the edge of failing. Again, these old, cheap ammeters have a habit of failing and creating a very bad short. I wold take it out and disaasemble to carefully inspect it
 

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Opel Rallier since 1977
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ON the flasher switch, it may be that the grease inside has gotten hard and glued it stuck in one position. I don't have a good solution for that... maybe someone else has managed to 'unstick' these. The ones in the 50 series cars can be pretty cantankerous after they get old, plus the plastic in the pushbutton will get brittle and break off inside and jam them up....
 

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Discussion Starter #48
Thanks for the input. Agreed, not realistic to put the issue down to a single incident. There were probably dozens of times I put stress on the system when I was working to getting it running.

I will keep an eye on the ammeter. I am looking to do much more work on the dash and electrical system. I am really in need of a donor dash. Mine is in rough shape and will look to swap it it then.

Matt.


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