FAQ |
Members List |
Social Groups |
Calendar |
Search |
Today's Posts |
#1
|
||||
|
||||
Rear defroster blowing fuse
Hey guys
I have a 69 Grand Prix with a rear defroster and every time I turn it on it blows the 25 amp fuse . Anyone have any ideas why ? Thanks |
#2
|
||||
|
||||
Electric grid or blower fan?
__________________
Ed 1968 GTO (Thanks Mom) 2006 Silverado 2007 Cadillac SRX 2015 Chevy Express |
#3
|
||||
|
||||
It’s the grid on the rear window
|
#4
|
||||
|
||||
Here is some info .
|
#5
|
||||
|
||||
Does it blow the fuse in Low or High or both?
Break the circuit up into sections. With the switch in the off position, disconnect the connector behind the rear seat. With a meter on the ohms scale check the resistance of both wires in each plug to ground. If you read 0 ohms on one plug or the other keep going to the next component, back towards the dash or towards the window, disconnect and recheck. If the circuit reads good check the programmer leg and do the same. Or if you have a handful of fuses keep testing at each break in the line that you make. If you don't blow the fuse when disconnecting the rear seat connector then you know the problem lies with either the relay or a possible short in the wiring leading up to the window. Or if you do blow the fuse then disconnect the harness under the dash and recheck. By opening up the circuit at different points you can isolate the faulty component
__________________
Ed 1968 GTO (Thanks Mom) 2006 Silverado 2007 Cadillac SRX 2015 Chevy Express Last edited by OG68; 10-23-2021 at 01:21 AM. |
#6
|
||||
|
||||
Try another relay. Quick way to narrow down its not that.
|
#7
|
||||
|
||||
I’m looking for one but hard to find
Relay GM #9798875 |
#8
|
||||
|
||||
Is it the same in a TA?
Rule #1, always buy 1 extra of everything lol |
#9
|
||||
|
||||
I don’t think so
I will take a picture in a couple hours for you |
#10
|
||||
|
||||
Lookup the new part #
|
#11
|
||||
|
||||
|
#12
|
||||
|
||||
Stop by your local GM dealer, that number you have may have changed several times.
Have him run the numbers on the locator. You never know. I recently found an EGR valve for a 78 ta recently by having my buddy run it on the locator. |
#13
|
||||
|
||||
I always like to troubleshoot before buying parts..but that's just me. OG68 is giving you good advice on using a meter.
__________________
Greg Reid Palmetto, Georgia |
#14
|
||||
|
||||
You need spare parts. Lol
__________________
🧩 Burds Parts, Finding those Hard to Find PCs, no Fisher Price Toys Here Just Say No To 8” Flakes F ire B irds 🇮🇱 |
The Following User Says Thank You to burd For This Useful Post: | ||
#15
|
||||
|
||||
Can never have enough of those!
Trying to find them in your stash is the hard part
__________________
Ed 1968 GTO (Thanks Mom) 2006 Silverado 2007 Cadillac SRX 2015 Chevy Express |
#16
|
||||
|
||||
You'll find that you need fewer of them if you troubleshoot before swapping them in! Especially in regard to electrical dead-shorts. That's a good way to let the smoke out of them.
__________________
Greg Reid Palmetto, Georgia |
#17
|
||||
|
||||
I would trace the wires going to the trunk area. One or both are shortening out on metal. Are they going under the sill plates or do the wires travel down the transmission tunnel? It looks like wires come in at the center of rear seat, I would start in trunk and trace wires from there.
__________________
going bandit-Reynolds style |
#18
|
||||
|
||||
Hey guys I’ve narrowed it down to a bad relay . I have one coming so I’ll keep you posted . The bad relay is chattering when I switch to low and then pops the fuse
|
The Following User Says Thank You to gto19 For This Useful Post: | ||
#19
|
||||
|
||||
Awesome. Figured it was was relay. Those are like $35 if you can find one on the shelf.
Trying a new relay is still cheaper than taking it in to have the elec checked. I’d look for a spare switch. BTW, I have decals for all the switches.
__________________
🧩 Burds Parts, Finding those Hard to Find PCs, no Fisher Price Toys Here Just Say No To 8” Flakes F ire B irds 🇮🇱 |
Reply |
Thread Tools | |
Display Modes | |
|
|