Author Topic: No power to 5amp fuse  (Read 1354 times)

Offline bd

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Re: No power to 5amp fuse
« Reply #15 on: July 18, 2022, 09:48:23 PM »
Standard OEM flashers are thermal relays.  They require a certain minimum threshold of current flow through them in order to cycle ON-Off-ON-Off-ON-OFF....  Having the rear lamps disconnected (or not grounded as the case may be) might decrease current flow through the flasher sufficiently to keep it from flashing.  That's why I typically recommend electronic flashers as service replacements since they cycle based on an internal oscillator that functions independently of the current demand placed on the flasher.  Either reconnect the rear lamps and try again or substitute a heavy-duty electronic flasher.

Have you measured the voltage at the horn as I suggested?  Isolate the dash wiring from the turn signal switch.  Disconnect the turn signal switch from the dash harness by unplugging the wide flat connector alongside the steering column behind and under the dash.  Then use a small jumper to momentarily ground the black wire in the dash harness connector.  Grounding the black wire should energize the horn relay and blow the horn(s).  Does the horn blow normally when doing this?

It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline Chevygold

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Re: No power to 5amp fuse
« Reply #16 on: July 29, 2022, 02:00:57 PM »
When my horn didn't work it turned out to be one of the connectors at the relay plug, it's tang wasn't holding it in place and it slid back so no contact, bent the tang a bit and pushed it back in the plug and all sorted!
Love these no cost fixes!