Backup lights flicker then off when shifting into R

[stratamarr]

Hello all, have a interesting problem and I couldn't find other thread with the same issue.

With my teenage soon as witness, when shifting from P to R, my backup lights briefly flicker on, but when fully in R, they are not lit.

So good news, the bulbs are fine, the wiring is fine, but there's something somewhere that needs adjustment.

[BobH]

Hello, assuming everything else is ok and all gears are selected without any problem, it looks like it may be your neutral safety switch, located on the firewall

Have a look on here

 https://www.sl113.org/wiki/Electrical/ReverseLights

You could check the wire cable connection is good, the wire that operates the lever on the switch, with no bends.  I don't know if these switches can be taken apart and the contacts cleaned, perhaps have a search to see if anyone has done this

You could also check the resistance on the contacts, pins 3 and 4, should read 0 ohms between them when in reverse.  Measure on the actual switch with the plug removed, if the resistance flickers, it might indicate that the contacts need cleaning, or the switch is failing

[Lorsar]

Most likely the neutral safety switch cable has a bend in it.  Since it flickers, the cable appears to be pushing the switch up a bit but it is not able to move it all the way into the reverse position.  I had the same issue.  You can disconnect the ball socket and move the switch manually to see that it works.  The issue is usually the section of wire attached at the shifter plate on the transmission.  If there is no noticeable bend in the cable, you can watch the cable while shifting into reverse and see if it bows.