Corvair Forum

Hello

I have been working and reading up from other posts about turn signal issues on Corvairs. I have been rewiring My 62' Rampside and continuing to have issues with rear tail lights. I am pretty sure it to be a ground issue however I thought why not throw out a quick message to maybe help my cause. I have all lights working and signaling on the front, I have running lights working in the rear and Brake light when the running lights are not on. My rear left signal works fine but can't get the right signal to work. I have replaced all wiring from the rear connector, replaced all bulbs and checked current to the front connectors under the dash. That all checks out good. I am going to continue replacing the wiring harness to the cab. However I want to ask if there is something obvious I might be overlooking.I am far from a electrical guru.

Any suggestion are welcomed.

I have linked all three pages from the 1962 shop manual supplement that show the Corvair 95 wiring schematic. Left clicking on this image will enlarge the schematic on the screen so that you can view it in detail and scroll around to trace a circuit.

I have also attached a copy of the appropriate supplement section that contains the individual schematics.

Power for the bright filaments in the 1034/1157 bulbs in the rear tail light housings comes from two sources that route to the TURN SIGNAL SWITCH: 20Y (Intermittent 12V DC from the Flasher Module in the Fuse Block) or 20N (12V DC from the STOP LAMP SWITCH at the brake pedal). The turn signal switch (in the neutral position) passes the voltage from the STOP LAMP SWITCH straight through to the 20V wire (Right-Hand Tail Lamp) and the 20P wire (Left-Hand Tail Lamp). When the driver steps on the brake pedal, the circuit is completed and both brake lights are illuminated.

When the driver moves the turn signal switch to either the right or left turn signal, the power source from the selected side is temporarily disconnected from the STOP LAMP SWITCH and is reconnected to the Flasher in the Fuse Block. The front 1034/1157 filament is simultaneously connected to the same flasher power source, and both the front and rear turn signal lamps flash intermittently until the turn is cancelled. (The rear 1034/1157 bulb filament on the opposite side remains connected to the STOP LAMP SWITCH, so that the rear stop lamp will illuminate continuously whenever the driver steps on the brake pedal. In this way one side can indicate a turn, while the other side can still indicate the application of the brakes).
Do the rear brake lights work when the tail (running) lights are on? If they do then the tail lamp socket ground is likely OK. The wiring harness from the turn signal switch to the rear sockets is the same for both the rear turn signals and brake lamps (on each side, respectively). So if both brake lamps illuminate when you step on the brake pedal, this confirms a good circuit from the turn signal switch to each rear lamp socket, through each bulb filament, and on to the socket ground.

If the turn signal flashes on one side, but not the other, this confirms a good power circuit from the fuse block and flasher to the turn signal switch.

Two things might disrupt the turn signal light on the right side:

(1) A faulty circuit or bulb on the same side, in the front. The flasher will only cycle on and off if it is properly loaded by TWO BULBS (front and rear) and the instrument panel turn signal lamp. If the front circuit or bulb on that side is bad, the current draw will be too low for the flasher to cycle properly, and it might be "stuck". You can confirm the condition of the rear bulbs and bulb circuits by simply stepping on the brake pedal. But the front bulb condition and bulb circuit must also be confirmed. A corroded socket, faulty bulb filament, bad circuit, or bad socket ground in the front could prevent the flasher from operating properly due to inadequate current draw on that side.

(2) A faulty internal contact inside the turn signal switch could prevent flasher power from reaching the front and rear turn signal lamps when the turn signal switch is engaged on the side that is not working.

If testing confirms that the front and rear bulb circuits are functioning properly between the turn signal switch and the bulb sockets, a bad turn signal switch may be the cause of the turn signal failure. (The function of the turn signal switch can be tested with a test light or ohm meter with the turn signal switch unplugged from the wiring harness. You will have to figure out which connectors on the socket are related to the flasher power and the front/rear bulbs used for turn signals (using the wire color code will point you to the correct connectors) With a continuity tester, you should be able to test for continuity between the flasher connector and the left or right bulb wire terminals. Moving the turn signal lever to the left or right should establish an electrical connection between the flasher connector and the bulb connectors on the selected side).

RIGHT SIDE TURN SIGNAL [20Y (Flasher) >> 20DBL (Right Front) and 20V (Right Rear)]

LEFT SIDE TURN SIGNAL [20Y (Flasher) >> 20LBL (Left Front) and 20P (Left Rear)]


http://www.corvair.com/user-cgi/catalog ... IN&page=87


Part number C861A: 61-63 VAN DIRECTIONAL SWITCH CABLE CASING = C8078 , WIRE = C8076

Weight: 0 lbs 6 oz
Catalog Pages(s): 87
Price: $ 35.75

Thanks for the info bbodie52. Much appreciated.

My problem on my -65 Corsa is the other way around. I have flasher both to the right and left but brake light only on the left hand side. I have replaced the socket and bulb to rule out any failure there. Could the problem be in the turn signal switch itself so it don´t let power go to the right brake light?

Boxer wrote:My problem on my -65 Corsa is the other way around. I have flasher both to the right and left but brake light only on the left hand side. I have replaced the socket and bulb to rule out any failure there. Could the problem be in the turn signal switch itself so it don´t let power go to the right brake light?

The two wires you need to be concerned with are labeled 20 DG (20 Gauge DARK GREEN) and 20 B/Y (20 Gauge BLACK with YELLOW STRIPE). They feed the right and left brake lights all the way from the turn signal switch at the steering column to the bulb filament on each side in the rear. Since the same exact bright bulb filaments support BOTH the turn signals and brakes on each side, they must be wired separately to be able to do both jobs. The turn signal switch in the steering column either feeds power to both rear bulb filaments simultaneously (from the brake pedal switch), or — when a turn signal is activated — it disconnects the brake pedal switch as a power source from the selected turn signal bulb and reroutes it to use the flasher unit at the fuse block as an intermittent (flashing) power source on the selected side only. (At the same time the front flashing signal bulb and the turn signal display bulb in the instrument panel are tied to the flasher output). This arrangement allows the brake bulb in the rear that is not indicating a turn to continue acting as a continuous brake lamp, which tells the driver behind your car that you are applying your brakes AND preparing for and approaching a turn.

Your wiring appears to be good all the way from the turn signal switch to each of the rear turn/brake filaments in the rear bulbs. This is proven because you stated that the turn signals work on both sides. However, you also stated that when the turn signal lever is in the neutral (OFF) position, your brake light only works on the left side. Since the bulb filament, ground, and wiring harness are already shown to be OK on the right side (proven by the functioning turn signal), and we know that both brake lights share the same common power source — the brake light switch at the brake pedal — the answer must be a faulty contact inside the turn signal switch in the steering column. If the contact that feeds the right side bulb from the brake pedal switch is corroded, bent or dirty it may be failing to reconnect to the rear bulb contact when the turn signal switch returns to the middle (neutral) position. If the switch cannot be repaired it will have to be replaced.

http://www.corvair.com/user-cgi/catalog ... IN&page=87


Part number C862: 65-66 & 64-65 FC DIRECTIONAL SWITCH

Weight: 1 lbs 0 oz
Catalog Pages(s): 87
Price: $ 60.50

Thanks Brad. I agree with you, the turn signal switch seems to be the issue. I will try to examine it today and see if it can be fixed, otherwise Clark´s will end up enjoying some more of my Corvair-money.

@Boxer: While you have your switch apart, here's a picture of the various parts inside the switch. With their functions in mind you can determine which contact needs cleaning or which lever needs reshaping. (Thanks to AZ Dave on CCF for the image)

Thanks cnicol!. Much appriciated

Found the little rascal. Both brake lights working again.

Amazing where you can find those little gremlins hanging out in a Corvair! Gremlins
Strange creatures which then spawn other creatures who transform into small, destructive, evil monsters. Commonly found residing in Corvairs! (Can also be found breeding in political party conventions — commonly called politicians, a.k.a. bureaucrats).