Turn signal indicator

[Hollar]

K20 1979. Right turn signal bulb in Dash won't work. The left one does. The right bulb is okay; can put it in left socket and it works. There is current (using a test light) in the right socket, but a working bulb will not light up in in it. Any ideas?

 

[cybrfire]

Prongs in the socket messed up and not lining up properly to the bulb?

 

[Hollar]

Good idea. I'll disassemble further to try to check that.

 

[dyeager535]

K20 1979. Right turn signal bulb in Dash won't work. The left one does. The right bulb is okay; can put it in left socket and it works. There is current (using a test light) in the right socket, but a working bulb will not light up in in it. Any ideas?

Using a test light...does it blink?

Can't recall if those are a switched ground or switched positive, with the test light you'd need to test both prongs, since you are assumedly using a separate ground, which is not testing the ground at the socket.

All exterior turn signals work as they should, correct? Bulb/socket issues at the exterior locations will manifest themselves in the indicator light.

 

[Hollar]

Using a test light...does it blink?

Can't recall if those are a switched ground or switched positive, with the test light you'd need to test both prongs, since you are assumedly using a separate ground, which is not testing the ground at the socket.

All exterior turn signals work as they should, correct? Bulb/socket issues at the exterior locations will manifest themselves in the indicator light.

Yep, it does blink, grounded to frame, and all exterior bulbs work, however, only when touching a certain spot on one side of the bulb socket, so it does appear that something is wrong with the socket. The other socket tests good on one side of the socket. I'll get the cluster out soon to see if it's repairable or get new sockets.

 

[dyeager535]

Pretty unlikely the socket is bad, it's just two bent pieces of metal snake through the plastic holder. Often the printed circuit is the issue, either where the socket fits, or where the connector mates up. The traces will delaminate from the plastic and move, which breaks contact. The metal legs in the sockets (where they mate up to the printed circuit) can be bent to create a bit more tension.

Unfortunately a relatively common issue with this design, be exceptionally careful removing the wiring connector, and when you disassemble/reassemble any of it, the traces don't bond to the plastic very well.

 

[Hollar]

Pretty unlikely the socket is bad, it's just two bent pieces of metal snake through the plastic holder. Often the printed circuit is the issue, either where the socket fits, or where the connector mates up. The traces will delaminate from the plastic and move, which breaks contact. The metal legs in the sockets (where they mate up to the printed circuit) can be bent to create a bit more tension.

Unfortunately a relatively common issue with this design, be exceptionally careful removing the wiring connector, and when you disassemble/reassemble any of it, the traces don't bond to the plastic very well.

Perhaps since I'm going to pull the cluster out, go ahead and replace the printed circuit and bulb holders?

 

[dyeager535]

I wouldn't unless someone has been in there and royally screwed it up. The solution is to hard wire everything in the cluster and get rid of the printed circuit, but that is not a quick job.

It's just a (relatively) bad design.

 

[urbex]

I found the PO installed cheap Chinese LEDs in all locations in my K5 in an annoyingly blinding, yet dim, blue color. When I pulled them out to replace them with standard incandescent bulbs, I found the bases on the LEDs were thicker than standard 194/168 bulbs, and spread the contacts in the sockets, leading to loose connections on regular bulbs. I ended up having to replace all the sockets on the back of the cluster, along with the running light sockets on the fenders that used 194 bulbs because of this. It might have been possible to bend the socket contacts back up a bit, but I didn't bother as I probably have a couple hundred of these sockets from tearing apart trucks over the past couple of decades, lol

 

[Hollar]

Pretty unlikely the socket is bad, it's just two bent pieces of metal snake through the plastic holder. Often the printed circuit is the issue, either where the socket fits, or where the connector mates up. The traces will delaminate from the plastic and move, which breaks contact. The metal legs in the sockets (where they mate up to the printed circuit) can be bent to create a bit more tension.

Unfortunately a relatively common issue with this design, be exceptionally careful removing the wiring connector, and when you disassemble/reassemble any of it, the traces don't bond to the plastic very well.

I'm an amateur regarding this sort of thing, just like to work on things . Based on my limited knowledge, I might try the printed circuit and all new bulb holders. I presume hardwiring may be a better option for someone such as yourself that actually knows what they are doing.

 

[dyeager535]

I'd at least pull it first to see if there is an obvious issue. No idea what the printed circuit runs, but new isn't going to be a whole lot better than what you have, unless someone has physically damaged yours.