I've done a couple 4 speed conversions now and have set up the reverse lock out and neutral safety switch but I've never changed the backup lamp switch and my backup lights work fine? I was looking on the M&H electrical website and saw it. Has anybody else used the back up lamp switch? Anymore info would be great?
I'm not sure what year vehicle you're working with, but the collar on the steering column controls the backup lights at least during the 1970 model year for Skylarks/Specials/GS for every transmission choice: manual column shift, manual floor shift, auto w/column shift, and auto w/floor shift. If you kept the back drive system that you had, you should notice your steering column collar rotating and your backup lights should work fine as you are observing.
1970 GS 455 The collar on the column turns since I have my reverse lockout hooked up and backup lights turn on but I'm curious why M&H sells a backup lamp switch for a manual transmission. In the picture it only has two prongs and the one on a column of an automatic car has 7 prongs I think? I have no idea what the other 5 prongs are for as everything on my car seems to be working fine?
The back up light switch on an automatic column is different than a manual trans column. The difference is the location of the plastic guide that is inserted into the column. When an automatic is in Park, the steering column is turned all the way to the left, and when placed in Reverse it is slightly turned to the right which activates the switch to turn the Reverse lights on. When a manual trans is in Reverse, the steering column is turned all the way to the left and if the automatic switch is installed, the lights will not come on as that is normally the Park position in an automatic. Not sure how your conversions worked without having to replace the switch unless you modified the switch mounting. As far as the different number of terminals on the auto vs manual switch, the reason is the neutral safety switch. There are two additional terminals on an automatic as the manual trans cars got a clutch activated switch. Not sure what the other terminals are for.
Thanks James Come to think of it now I do recall my brother and I messing around with the automatic switch on the column one late night before the safety inspection.
I am upgrading my 67 GS 400 4spd I recently purchased and wondered why the backup lights did not work. Put it up on a lift and lo and behold there was no backup light switch where it should be mounted on the transmission. I went to OPGI, Fusick Parts, and Year One and they all had the switch with mounting bracket and showed photos on how it mounts and connects to the linkage.:laugh: I also had to purchase a wire harness extension to connect to the harness at the dashboard. I have it installed but I am waiting for my gearshift lever to come back from the chrome shop so we can bolt it in and start shifting!
I think the 67 model was the last year for that trans set up. Same for Olds. When GM moved the ignition key from the dash to the steering column in the 68 model, the back up switch was also moved from the trans to the steering column. In his first post the OP, I thought, was thinking of the pre 68 trans set up.
So I had a closer look at some steering columns today and noticed that some backup lamp switches have 6 prongs and some have 4. I couldn't find a pattern of what was what as some 350 columns had 4 and 6 and some 455 ones had 4 and 6 that's if I had the columns labelled properly. I'm more curious now then anything as to what the difference is? Anyone out there know?
