I have a 1994 gmc w4500 and cant find the turn signal relay does anyone know where it is???

There isn't one. The function is done by the Body Control Module (BCM) along with lots of other functions.

Where is the turn signal relay on a 2006 Chevy Colorado?
The turn signal is controlled by the BCM (Body Control Module) that is located at the passenger side kick panel.
May 21, 2014

2006 Colorado turn signal relay? where is it - 355 Nation

Known issue

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go to an accredited auto electrician for electrical work
it may be a switch problem but I think that there is no power to the light relays ( switch or fuses)
if that model has a light control module , it could be that

the brake light switch powers the wire which goes to the turn signal switch. So I think if the turn signals works, then the turn signal switch is bad. Check for power at the wire going from the brake switch to the turn signal switch. . Since you didnt tell what year or model the truck is, I cant tell you what the wire color is.

To find the FLASHER on 1994 GMC Truck C1500 1/2ton Sub 2WD 5.7L TBI 8cyl. the Flasher is located: Front seating area, driver side, under dash, driver side of steering column, mounted in relay bracket

Application: Hazard flasher

Turn SIgnal flasher is one independent unit.

Hope helps-

if your turn signals are not working it may be the flasher unit is faulty,it is under the dash on the drivers side,it could be a cylinder or a square unit about 2" long with a connector plug on the top.....hope this helps.....cheers

the turn signal relay is clipped under the dashboard.It is clipped to sheetmetal.You have to look it is almost hidden use a light remove panel and look under dashboard

Code 78 refers to the secondary fan relay circuit, I would start there, you might have a short in that circuit, or an open, or bad relay. Hope this helps, let me know

you have two options one your relay is bad that is also you hazard switch replace that first the cheaper of the two fixes other one is the turn signal stalk itself is bad. that you might want to take to a shop

Most times the relay is in the fuse box or under the dash by the steering column.

call junkyards for a new 1. had the same prob n had to b replaced