Indicator/ Hazard Flasher Relay problem and solution
 

Hi everyone,
My 1977 'S' 2.7 had an indicator /hazard flasher relay problem. Here's the car in question
http://forums.pelicanparts.com/uploa...1461700801.jpg

When not in use the indicator lights on the dash board would always both be 'on', though not fully just dimly. Using the turn signals would work fine ie the lights on the car would flash correctly but the dash lamps would illuminate brightly and then the opposite indicator lamp would light dimly. This was the same for turning left as it was for right. Did some searching on this forum and apparently this problem has happened before. Caused by a stray voltage constantly feeding the indicator lamps on the dash. 'Targa80' has a modification for this problem, by bypassing the ground feed to the lamps, which is something Porsche also did on later models. His informative post is here http://forums.pelicanparts.com/porsche-911-technical-forum/819548-flasher-hazard-mods-my-80sc.html
My problem was exactly the same so I thought I'd take a look inside the relay to find out what it might be. Luckily I had a spare working flasher relay to use for the investigation. Here are the two relays with the covers removed. One working fine and the other not http://forums.pelicanparts.com/uploa...1461698420.jpg

After a bit of probing I found that the only voltage difference between the two units was between these two contacts found on the secondary smaller relay unit (I believe this one drives the dash lamps while the larger primary unit drives the exterior car lamps, though please correct me if I'm wrong) Anyway, I noticed a small continuity between these two contacts marked red and green in the photo. My thinking was that there shouldn't be any connection between these when the relay was in the off position.
http://forums.pelicanparts.com/uploa...1461699007.jpg

To make sure I de-soldered the unit off the circuit board on the faulty unit and swapped it for the good one and...the fault was cured. So definitely a faulty secondary relay unit. Here is the de-soldered relay unit in question http://forums.pelicanparts.com/uploa...1461699297.jpg

Next I carefully drilled out the rivet holding the contacts onto the coil, using an 3mm drill bit.
http://forums.pelicanparts.com/uploa...1461699402.jpg

Sandwiched between the two contacts are a couple of insulating screens (red arrows) which should isolate the two from each other.
http://forums.pelicanparts.com/uploa...1461699755.jpg

I reassembled the parts as before only this time using a nylon non conductive bolt to replace the drilled out rivet (Red arrow).http://forums.pelicanparts.com/uploa...1461699909.jpg

Next, resoldered the unit back onto the circuit board and checked that there was no voltage leak between the two contacts (marked with red and green arrows) while the relay was in the 'off' position http://forums.pelicanparts.com/uploa...1461700109.jpg

Finally, fitted the unit to the car and it almost worked correctly! The thing to make sure of is that when the relay is energized and in the 'on' position (here I'm simulating this by pushing the contact over with a pencil) it has to make contact with both the small and larger contacts in order to function correctly. (Marked with red arrows)
http://forums.pelicanparts.com/uploa...1461700496.jpg

If you happen to have the same problem then maybe this fix will help. All the best -Mark