| ID | Status | Date | Year | Make | Model | Transmission Type | A/C Controls | Public/Private |
|---|---|---|---|---|---|---|---|---|
| #16512 | Closed | 1990 | Chevrolet | 2500hd 4x4 extra cab | public |
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I have a 1990 Chevy 2500hd 4×4 extra cab 5.7L 350. I started having a wiring issue with my passenger side tail lights/brake light/turn signal. (There are 3 bulbs tail light, brake light/turn/ tail light bulb and backup bulb. I’ve changed out the bulbs and bulb circuit board. Now I have tail lights with both bulbs but the middle bulb (turn/brake) doesn’t flash for turn or brake. I have checked plugs with voltmeter and all 4 register 12. Bulbs are new and work in other taillight. I’m stumped….. |
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I am assuming from your description that you have tested for power on the yellow wire and ground on the black wire. I prefer using a home made test light using a 9006 headlight bulb and it’s harness connector. That allows for a 5 to 7 amp load on the circuits to root out any weaknesses. Place one lead on the black wire terminal and the other on the yellow wire terminal. Do not force the wire into the terminal and damage it. Also you will want to confirm that the terminal is not already damaged (collapsed). Confirm the brake and turn signal operation. An assistant is very helpful for activating the switches while you look at the light. If both signals are there the circuit board is likely bad. There are many issues with the replacement circuit boards and I would recommend trying a different brand. |