IS250blue

Hi guys,
My gx got its Radio No.2 30A fuse kept blowing up. It made the gps/climate control screen went dark after roughly 3-5 mins use. I replaced this fuse three times already, and the same problem kept coming up. everything is stock.
Please help.
thanks

chiph9

Probably a wire's insulation got cut by rubbing against a piece of steel.

Inside the dash, about where your right knee is when driving, is a very large connector that many of the radio circuits run through. Disconnect that and see if it still blows. If it does, you know the problem is from there to the fusebox. If it doesn't, the problem is from there to the screen. You might get lucky and smell the problem...

Otherwise, you'll have to trace it down. The wiring diagrams are available on techstream - I believe you can buy a couple of days subscription (hint: stock up on printer ink)

Chip H.

tz693

Go to the service screen to run the diagnostic.

IS250blue

Thanks guys so much for your inputs. i will try it tomorrow. The funny thing is when I replaced the fuse, the first one blew right away. The second one blew when I got to the climate control. The third one blew 8 mins while I was playing radio. Is it odd about the inconsistency of these fuses?

IS250blue

Hi Chip,
Do you know how does that connector look like, how many pins is it? and can I crawl underneath the steering column to reach it?
Thanks

chiph9

You'll have to remove trim pieces. Search on Youtube for "How to remove radio / navigation / Climate Control from Lexus GX470" At 1:25 you can see a white plastic piece by the volume **** - remove that bolt to remove the connector.

Chip H.

IS250blue

Yellow wire from the big connector
Hi chip
i opened up the nav console again. I found two wire from the audio connection behind the volume **** swollen its plastic cover. After disconne this hub, the fuse stops blowing so far.Do you think if i run a new wire will solve this problem?
Thanks in advance.
Ken This is the end that connects to the nav/audio. The orangeish shield swollen up
This is from the big connection behind volume ****

IS250blue

After open up the white covers, i found total 3 wires with swollen shield in brown, orange, yellow

chiph9

I don't have a wiring diagram so I don't know what those wires are for, but that certainly seems suspicious.

I had a look on my usual Lexus parts website but didn't see a part for that sub-harness - if you can see something that looks like a part number (probably on a white tag, or maybe stamped/printed on the connector), it might be worth seeing how much to buy just that harness.

Something else to try is to unplug that harness from all the radio equipment and use an ohmmeter to see how much resistance those wires have.

Otherwise yeah, replacing those wires would be the next thing to try.

Chip H.

IS250blue

Hi Chip,
So today I redo the unplug the big white connector,and turn on the car. for some reason, the screen didn't turn on at all. I guess the problem must be from that big connector to my fuse box. The only new thing I added to this car was the viper alarm. Do you know where can I find the viper may cause the overload?
thanks

chiph9

Alarms can cause all kinds of strange electrical problems. You'll need to take it back to your alarm installer and ask them to double-check their work.

Chip H.