So I checked the brake lights/turn signals today. I replaced the LF and LR turn signal bulbs, then tested. No LR blinker. Here's the results of troubleshooting: * Left and right brake lights work. * Right rear blinker (and front) works * Left front blinker works (and in the dash) * Left rear blinker does not work. * No voltage to the left rear bulb connector when the left turn signal lever is pushed down (specifically the green/white wire). I disconnected the harness connector located in the trunk, right behind the rear seat. I checked for voltage at the male connector end (this checks the harness section coming from the dash routed under the rocker panel and to trunk). * No voltage on the green/white wire. So I find a wiring diagram for the car on the 'Net and I see that there is a dedicated positive wire at the turn signal switch located on the steering column for each corner (LF/RF/RR/LR) of the car. There is another harness connector at the left front kick panel, just under the dash. I will check for voltage at that connector tomorrow (for the green/white wire). If there is no voltage there, my assumption is that either the section of green/white wire from the turn signal switch to the harness connector (left front kick panel) is bad or there is a malfunction of the turn signal switch itself. So after I've bored you with all this, I'm wondering if my analysis is correct? Is it possible that just one connector within the turn signal switch is bad (dedicated for the LR bulb)? Is it more probable that the section or green/white wire from the turn signal switch is bad? Anyone have any other insight that I've missed?
I'm not very well versed on the electrical problems,in fact,I hate them.Just reading your post it seems that you have been doing some good trouble shooting.I would only suggest a continuity check for the trunk portion of the wires and one for the one ahead of it,that can locate a short.Good luck with it and welcome to the site.
IF... the bulb in question lights with the brake on but does not light when asked to flash.... you most likely have a dirty/bent/broke/melted(?) terminal in the turn signal switch. if the bulb in question is a blinker only bulb ....we have lots of places to suspect. are there more than on blinker bulb on each side or the rear of the car? why not post a link to the schematic you are using so we can see what you are talking about. colors did a few changes over the 60s so help us be on the same page(literally) as you.
i found a 64 schematic here. http://www.tocmp.com/tOCMP/wiring/5765wiring diagrams/buickindex.htm i cant find a green with white for anything!!
it looks like you probably have a 63 harness ... no biggie. assuming you do ... here we go...ou: when working correctly, with no turnsignal on and the brake pushed, your brake lights light because the resting state of you turnsignal switch has DKBlue connected to DKGreen/wht (left) & DKGreen/bk(right) (bright) filiments in the rear of the car. NOW... lets say you are driving and apply your brake and turn on the left signal.. the turn signal switch removes the DKGreen/wht wire from the DKBLue wire and attaches it AND the DKGreen (front left) wire to the Pink wire. the Pink wire has a flasher in line so whatever bulbs get connected to it will flash while the key is "on". so if you know the brake light works for the left side and the rear turn signal doesnt, but the front signal does ... the problem has to be what i have labeled terminal "B" in the picture. its getting disconnected from the DKBle but aint getting reconnected to the pink wire's terminal when left turn is requested .... try this, have someone watch the rear left when you have the turn signal(and key) on. slightly pull back and push forward while wiggling the lever a little ... see if it lights/flashes any. that would be a sign of maybe just needing cleaned or tweaked. keep us posted .
That's the schematic I used, but I discovered (I have another post describing this discrepancy) if you look at the 1963 schematic for the LaSabre (at that website), you'll see that all colors are correct for my car
Yes ... I'm using the '63 wiring diagram too So I get in the car and while holding the brakes on I turn the Right signal on and the Left signal on in turn: * Right side blinks, left side shows brakes * Left side doesnt blink *and* shows no brake light. BTW - this car uses a single 1157 bulb on each side, so the single bulb handles brake light and signal. So next I tried your suggestion - turn the left signal on and wiggle the turn signal lever - WOO HOO! Suddenly the left rear turn signal worked! (but the front stopped ) So I wiggled some more and then both the front and rear bulbs worked!! I actually "wiggled" the lever in a circular motion - going forward/back and [slightly] up/down didn't work, but in a circular motion, it cleared it up. So I guess we can assume a couple of things: * Loose connections at the switch for the left connectors? * Switch is going bad? * Maybe spray some electrical spray into the switch's area, in the hopes that'll clear it up (without having to remove the steering wheel to physically access the switch). Thoughts? Oh, and "yuk" - thanks for staying up till 3:30am on this one - it's much appreciated
try the contact cleaner and turn off and on and wiggle(the lever, not yourself) while spraying it. if that helps and can buy you some time.. start shopping for a new switch so you can have it ready to install i the near future if needed. if you have never replacred one, i suggest you research it and talk with some people who have. btw... do you know that the dual filiment in the 1157 bulb does three things? one filiment is bright for turn/brake use and the other filiment is dim for taillight use .... just wanna make sure thats clear. if your car has cornering lights(i dont know if they were even available in 64), it will be a different switch than a car that doesnt. a car that doesnt have them can use either switch.
@gstewart - I'm sure eventually I will have to. @yuk - good idea on searching folks out who've changed the switch out. I do have a Motor's manual picked up back in the 70's ... I think it details how to get to the switch. No cornering lights on this one. Well, I sprayed CRC QD Electronic Cleaner in where the turn signal lever goes into the column, then sprayed into the ring gap (between gear selector collar and the signal collar) from various angles and moved the lever up and down about 20 times. I allowed the spray to dry (dries pretty quick) then moved the signal to right and left and it comes on now, fairly consistently. A first attempt with only a couple of quick sprays, when I selected left signal, over and over, sometimes front and rear would come on, sometimes only the rear, and sometimes only the front (I know when the front doesn't work, cause the dash signal doesnt blink). (BTW - the front always worked consistently prior) But the second, more thorough cleaning seems to have done the trick. In the meantime, I'll be on the hunt for a switch. Thanks for all the help !!
your welcome for advice. i love diagnosing electrical stuff. when you have it apart to change the switch try to get a good look at the upper steering column bearing. see if you can get a little lube in it. it may get dried out if the CRC crept in there any.
