1998 Buick Century • 80,000 miles

1998 buick century, left rear signal and brake light does not light, the parking light does work, the socket is new, it shows voltage at the wire when the signal is on but shows no voltage at the wire if the bulb is in the socket, tested for continuity from wire to the contacts in the socket and it is all good, tried a new ground and that did not work. The right rear and both fronts work fine. I am wondering if it is the hazard/signal switch or the brake light switch.
June 30, 2012.

You have a high resistance in that circuit.
You could have a high resistance contact in the signal switch, but a more likely cause is a corroded connector pin in the wiring harness. I'm sorry I can't access the wiring diagrams, but to verify whether it's the switch or wire, you would have to find that wire at the signal switch connector and apply 12 volts from the feed wire or directly from the battery. If the bulb lights up, suspect the switch. It it doesn't light up, follow that wire to see where voltage is lost.

Jul 1, 2012.
Thank you for the reply, it makes a lot of sense, hopefully it will be something simple and not a bad connection somewhere that is hard to get to.

Jul 1, 2012.