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I don;t want write an essay here, but I've tried to make AUX input to my wifes' 97 ES300, followed these instructions from another thread... https://www.clublexus.com/forums/es-...d-changer.html
..I needed also add. ground and +12 because I'm installing bluetooth receiver instead of just 1/8" aux in port.
By mistake I touched 12v wire to the radio chassis. No spark or anything, but I don't have now 12v on three terminals in the connector. Trying to locate radio fuse, I did it but all radio fuses are fine. Checked ALL the fuses (engine compartment, driver side compartment) - all OK. I am bit confused, put the car back together without running audio system just to make it driveable. Only one thing comes to my mind that's radio amplifiers' own fuse.
But
1) where's radio amplifier and how I get to it (was told in a glove box compartment, but I have CD changer there?) -
2) does it have its own fuse?
Or maybe another solution, am I missing something?
Where did you take 12V for the Bluetooth device?
What particular wire did you touch to the chassis?
What three terminals are you referring to?
From the schematics, the radio is powered from the amplifier, but the amp doesn't have a separate fuse, it all is powered from the 20A RADIO NO. 1 fuse. Below is a pinout for the Radio Connector, Pin 4 is for your Main Power for the Radio, Pins 11 and 12 are for your Ground, Pin 3 is a Signal voltage to turn on the radio when the ignition is turned to ACC position. If there is no power, go from the beginning - use a Test Light to make sure that the power is coming and leaving the fuse, then that it comes to the amplifier, pinout for which matches the radio for the aforementioned pins. If there is 12V on Pins 3 and 4 when the ignition is in the ACC position, then you may need a new radio.
To visualise, see my diagram below:
I took the power for BT device from +B (and ground below).
Those circled in blue were the audio connections.
When I checked voltages, in non running car ( no key), I had +12V on +B, on ACC and on ILL, so those 3 pins near each other, I decided to run BT from "+B". But when I cut the cable, it touched radio chassis. I saw that but no spark or any other effect was there co I continued to do the wiring. unfortunately I have no voltages on pins +B / ACC and ILL... and it's measure of course before it splugged to the radio unit. All fuses are Okay.
Can't see from shcematics if all those 3 pins get 12V from the audio amplifier? If the answer is YES, and all fuses are okay, and no fuse in the amp, it's more likely amp is shot, right?
B+ Terminal is designed for the radio, not for a whole lot of other stuff, that's what I told you about in your previous post, though it does depend on the power rating for the device you are using.
The description sounds a bit off, ACC pin should only be powered when the key is in the ACC position, otherwise your radio would always be engaged. ILL should only be powered when your Light Stalk is switched to TAIL position, since it engages the interior illumination. Try using a Test Light instead of a regular multimeter, it is much more precise.
As for the B+ terminal, you will always have a chance to swap out the amplifier, but before that, you need to make sure that it is indeed bad. The terminal that sends the power from the amp to the Radio is in the same spot as for that radio (connectors are the same), Pin that supplies voltage to an actual amplifier is marked below. Check that the power comes to the amplifier, but doesn't leave to the Radio, which would indicate that you should be on a lookout for an amp. If there is nothing coming to the amp, or the power actually leaves to the radio, then it is not and amplifier, but rather a fuse or the wiring.
I deafinitely had power on 3 those 3 terminals with all the wiring unplugged from the radio and key off.
I've driven this car only few times but didnt notice something odd with radio/lighting - all OK I'd say (and VERY GOOD sounding audio system!) ILL could be +12 because I had open doors when worked on that, so interior lights were on?
Anyway, many, many thanks for that power amp schematic. I'll try to check it over the weekend. It's hard for me to beilieve that the radio itself and power amp does not have its own fuses. Very strange, I'd see it for the first time ever in a car. That kind of "short" may happen over time even inside connector, so it would blow power amp instantly? That's bad... Do you know, by any chance if power amp have some sort of diode (burnt) in the power section? It may be just that? also, is the PIN4 on PA getting constant +12V even with the key off?
And what comes to my mind now - does that all 3 pins on radio connector gets their voltage from PA?
Sorry for a late update, but I had time today to check everything.
1. I located and removed power amp from glove box compartment
2. It does not have any external fuses, but there is VERY SMALL (like 3mm width) internal fuse that looks like a SMD resistor, labeled "5A" around power transistors. It looked right but measued no conductance. I have soldered 5A regular fuse to the pins of it.
3. Power is back everyhwere now! So when you have all fuses checked and your radio is still not powering, check that little thing. As far as I remember, radio fuse is 20A, so this 5A internal power amp fuse will go first I suppose.
Sorry for a late update, but I had time today to check everything.
1. I located and removed power amp from glove box compartment
2. It does not have any external fuses, but there is VERY SMALL (like 3mm width) internal fuse that looks like a SMD resistor, labeled "5A" around power transistors. It looked right but measued no conductance. I have soldered 5A regular fuse to the pins of it.
3. Power is back everyhwere now! So when you have all fuses checked and your radio is still not powering, check that little thing. As far as I remember, radio fuse is 20A, so this 5A internal power amp fuse will go first I suppose.
Huh, live and learn I guess, never knew there was an internal fuse in the amplifier.. It actually could've been one of those resettable fuse things, since I can't see any other reason for Toyota to hide it within the amp housing.
06-27-21, 06:43 AM
No power to radio unit... all fuses OK
