No backup lights...

[acarlson]

I posted this on the other forum, but someone here may be able to help.

I won’t go into the history of this problem. Lets just say my backup lights have never worked.

I have been told that I’m supposed to have a 1/4” steel ball in the backup switch socket in my ‘66 4-speed. That’s not there.

So, I really need 2 things:

1. The correct backup switch ball for a 66 4-speed

2. The connector which fits the terminals of a 66 backup switch.

If you have either or both, PM me and let me know what you want for them.

Thanks.

[bbodie52]

The backup light system for the manual transmission is a fairly simple circuit that should be easy to trace with a multimeter, perhaps by substitution
to verify each segment's functionality from the rear backup lights looking forward, through the engine compartment multiconnector, to the transmission switch, and forward to the power source. For example, if you separate the two halves of the engine compartment multiconnector and identify the backup light terminal within the connector, would applying 12 VDC there cause both rear backup lights to illuminate? Is electrical continuity good and verifiable from that connector back to the bulbs to cause them to illuminate? If that segment is confirmed, can the next segment to the transmission backup light switch also be confirmed? Can that switch be manually operated by hand to cause it to function and confirm electrical continuity to the rear lights? (If so, screwing it back into the transmission and confirming that the switch is mechanically activated/closed by shifting to REVERSE should also be easily verifiable. (I am not aware of any ball bearing between the transmission and the switch). If the switch and wiring is confirmed from the transmission back, the final segment going forward would be to confirm with a multimeter if the wiring harness is actually tapping into 12VDC (switched by the ignition switch to provide power only in the ON position of the ignition switch, I believe). This form of troubleshooting and fault isolation should lead you to the non-functioning segment(s), so any faulty portion can be corrected and you will end-up with a fully functional backup light system in your Corvair.

I have included images and schematic diagrams that may be helpful in helping you to visualize and test all of the portions of the backup light system in your Corvair. If you have the 1966 supplement to the 1965 Corvair Chassis Shop Manual, the 1966-specific transmission diagrams and electrical schematic diagrams should help a lot. Unfortunately I don't have all of those diagrams and photo images to display here.


1966-69 3 and 4-Speed Back-Up Switch


1961-1965 4-Speed Backup Light Switch

Backup Light Switch - 4-Speed Manual Transmission - 1961-1965

Backup Light Switch - 4-Speed Manual Transmission - 1961-1965.jpg (62.32 KiB) Viewed 482 times

1965 Corvair - Four Speed Transmission Backing Lamp Assembly Diagram

Left-click the image to enlarge for better viewing. Click a second time for maximum enlargement...

1965 Corvair Monza Full Schematic

[acarlson]

Brad,

Thanks but I have been through all that. The switch is not working with the trans in reverse. Take the switch out and manually push the contact on the end and it works fine. I'm told there is supposed to be a 1/4" steel ball in the transmission socket which presses on the end of the switch. I'm missing that.

Also, if you look at the picture you posted of the '66 switch, you'll see the wiring contacts are just solid posts. There must be a connector which fits that but I don't have it.

[bbodie52]

Clark's appears to list the following wiring harness as available with or without Backup (page 98). I did not see any sub-harness or pigtail associated with the 1966-69 transmission backup light switch. HOWEVER, You might consider using the 1965 and earlier 3-speed tunnel switch assembly that is triggered by movement of the shift linkage tube within the tunnel, and abandons the transmission-mounted switch altogether. I believe you would still have to fabricate and splice a connection to the rear engine compartment harness to link this tunnel switch to the rear engine compartment factory harness, and connect the forward portion to the existing power source under the dashboard.

You might need to communicate with Clark's to see if there is some harness that connects to the terminals on the transmission switch. I don't know if the harness described below simply omits the Powerglide shift lever portion, or if it includes a segment that connects all the way back to the manual transmission. But again, the simplest and least expensive substitute might be the tunnel switch "Fix-it Kit".



https://ssl.corvair.com/user-cgi/catalo ... ow_page=98

DASH (Fuse Block) HARNESS: This is the main harness under the dash connected to the fuse block. Complete with fuse block, all correct wires and connectors. This is a critical harness and almost impossible to find a good used one. The 1960-64 dash includes the instrument light sockets, etc. For the 1965-69, the instrument harness was separate. We try to keep all of these in stock.

Part number C9149: FUSE BLOCK HARNESS-66 EXC A/C & CORSA** *WITH STD TRANS

Weight: 4 lbs 0 oz
Catalog Page(s): 98
Price: $ 419.50




https://ssl.corvair.com/user-cgi/catalo ... w_page=84B

Backup Switch Substitute

Part number C8379: 4 SPEED BACK UP SWITCH FIX-THEY LEAVE OLD SWITCH IN PLACE-THIS WORKS OFF SHIFT ROD

Weight: 1 lbs 0 oz
Catalog Page(s): 84B
Price: $ 44.30


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More possibilities...

Backup switch repair new

http://corvaircenter.com/phorum/read.php?1,1116570

[acarlson]

Brad,

Those are good suggestions and if all else fails I may end up using one of them. The steel ball is not a problem - I can get one of those from a number of sources.

In my effort to troubleshoot the backup light problem, I discovered that a previous owner had installed a '65 backup switch in the '66 4-speed. As a result, I just ordered the correct switch from Clarks (which also didn't work). So, having just bought the correct switch, I'd like to get it working rather then spending more $'s on another solution. The pig tail is the missing piece for now...

[terribleted]

Brad,

Those are good suggestions and if all else fails I may end up using one of them. The steel ball is not a problem - I can get one of those from a number of sources.

In my effort to troubleshoot the backup light problem, I discovered that a previous owner had installed a '65 backup switch in the '66 4-speed. As a result, I just ordered the correct switch from Clarks (which also didn't work). So, having just bought the correct switch, I'd like to get it working rather then spending more $'s on another solution. The pig tail is the missing piece for now...

That "pigtail" is a large round cast rubber boot with 2 contacts potted into it. you will only find it used from someone like Steve Morton or Corvair Ranch or similar place that has parts cars laying around to pull one out of. I am sure there is some common female connector that could be pushed on those posts to make the electrical connections. They could likely even be done carefully with solder if need be.

I have the ball in a bad trans I have here. If you would like it, I could be persuaded to package and mail it to you for $10 for the trouble and postage. PM me if you like.

[acarlson]

Thanks Ted ! I may take you up on that or I might just take a road trip down to your shop (I've been there once before). I'll let you know.

I've also emailed the Corvair Ranch - they may have a cable available. Haven't heard back from them yet.

[doug6423]

Long story short.

I went through the same thing. Replaced switch, bulbs, housings, even ran extra ground wire to the housings, checked and cleaned other ground areas, new wiring harness in the engine compartment, new wiring harness in the tunnel... and still nothing.

I sent a picture of the fuse box on the other forum and someone noticed I had two wires reversed.....

Problem solved. Backup lights have worked ever since.

[terribleted]

Thanks Ted ! I may take you up on that or I might just take a road trip down to your shop (I've been there once before). I'll let you know.

I've also emailed the Corvair Ranch - they may have a cable available. Haven't heard back from them yet.

wont be $10 if you come here for it you can simply have it for free.