Still no turn signals Options

[silverteener]

We'll..

I got another hazard switch today and still have no turn signals. I have replaced the turn signal lever and put a new relay in. I also checked the light bulbs and they are 1157's. I found a ground under the dash above the fuse box and it is tight. This thing is really starting a piss me off. I'm thinking it's going back on jackstands til next year. I'm at a lose and there is no one around here to take it too. Any more suggestions? It's a 72 that I would like to (IMG:style_emoticons/default/ar15.gif) right now!

[Spoke]

It's a real bummer that this issue has been plaguing you so long. I redrew the turn signal portion of the schematic and simplified it a bit so it is easier to see the important connections.

Bare with me as I familiarize myself with this circuit. There's basically 4 components involved:

1) 4-Way Flasher Switch
2) Turn Signal Switch
3) Flasher Relay
4) Light bulbs

Power comes to this circuit through either fuse 9 or 11 depending on whether the 4-way flasher switch is active. Fuse 9 is switched power; that is, it is powered only when the ignition switch is ON. Fuse 11 is powered all the time. The 4-way switch is shown in the OFF position.

When the 4-way switch is pulled, power comes from Fuse 11.

12V power then goes to the Flasher relay on the RED wire; pins on both 4-way switch and flasher relay are #49. The flasher relay sends 12V power to the turn signal switch and the 4-way flasher switch on pin #49a.

When there is a load on the flasher relay pin #49a, it will click on and off, thus blinking the lights. A load is placed on this pin when either the 4-way flasher switch is pulled or the turn signal stalk is put in the left or right position. The load is the turn signal light bulbs.


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TESTING THE CIRCUITS
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If I were to walk up to your car right now to help you, this is what I would do the following in this order. You may have done some of these already. One of these steps will fail and thus you will come closer to isolating the issue. These steps will not solve the issue, just isolate it.

1) Check the wiring as shown below. Look at each component and make sure each colored wire is connected to the pin numbers shown below. The relays and switches have these pin numbers embossed by each pin.

2) If all connections look correct, then start to isolate each part of the circuit one by one. Follow each of the following steps assuming each is ok. If any of the measurements show trouble, you have found the issue; stop and investigate.

3) Start with the switch pins 15-30-49 of the 4-way flasher switch. This is a very simple circuit. 12V power to pin 49 comes from 15 (Fuse 9 with ignition switch ON) or from pin 30 (Fuse 11 with ignition switch ON or OFF). Pull the RED wire off of the the 4-way flasher switch pin 49. Turn on ignition and measure 12V from pin 49 to ground. Turn off ignition and measure 0V from pin 49 to ground. If this is ok, then this part of the circuit is ok. Pull the 4-way flasher switch and again measure 12V from pin 49 to ground.

4) Turn off ignition, turn off 4-way flasher switch. Replace the RED wire on pin 49 on the 4-way flasher switch.

5) Pull the RED wire off of the flasher relay pin 49. Measure the RED wire to ground. With the ignition switch ON, measure 12V. Turn off ignition and measure 0V from RED wire to ground. With the 4-way flasher switch pulled, measure 12V. If OK here, the RED wire to pin 49 is ok. Turn off ignition and push in 4-way flasher switch. Replace the RED wire to pin 49 of the flasher relay.

6) Pull the wires off of pin 49a of the flasher relay. Measure the pin 49a to ground. With the ignition switch ON, measure 12V. With the 4-way flasher switch pulled, measure 12V. If OK here, the flasher relay is ok. Turn off ignition and push in 4-way flasher switch. Replace the wires to pin 49a of the flasher relay.

7) Check 4-way flasher switch: Pull the R and L wires from the switch. This removes the lights from the circuit. Pull the switch and measure 12V from R to ground and L to ground. This will test all parts of the 4-way flasher switch.

8) Check the light bulb wiring: Remove all the light bulbs; front and rear bulbs and the dash indicator bulbs. Pull the wire off of pin 49a of the flasher relay. With ignition off, 4-way flasher switch off, and turn signal off, measure resistance (ohms) from the pulled wire to ground. This must be an open circuit. The only path to ground through this wire are the bulbs. If this is ok, then wires to the 4-way flasher and to the turn signal switch are ok.

9) With the wire on pin 49a of the flasher relay still pulled off, put turn signal to the left and measure resistance (ohms) the pulled wire to ground. This must be an open circuit.

10) With the wire on pin 49a of the flasher relay still pulled off, put turn signal to the right and measure resistance (ohms) the pulled wire to ground. This must be an open circuit.


Which one of these steps fail?

If none of these fail, replace the wire on pin 49a of the flasher relay. Turn ignition on and try the turn signals. Try the 4-way flasher switch.

If things are still ok, replace ONE bulb, any bulb then try the 4-way flasher switch and the turn signal switch. Continue replacing one bulb at a time and retry the turn signals.