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3 Posts
Discussion Starter · #1 ·
Hoo boy... This is a brahma...

So about a month ago I was faffing about putting a new USB/Cigar lighter point on my T3 Prius, if you are aware of this bum basic model the only Cigar lighter socket is in the centre line arm rest box... I needed one on the dash for my satnag so I set too, stupidly I had the radio on, net result eventually the 12V battery went flat and that is when the fun started.

Now. I put the "magic key" in press the start button and the dash board lights up for about 1 second then it all goes dark. If I hold the start button in eventually the centre screen will light up but will show the traction battery level meter as completely empty. And this is where I went down a rabbit hole.... I firmly believed it was because I had killed the 12V battery that this effect with the dash was happening. So I checked every single fuse, took the dash apart again (getting quite good at this) to make sure I hadn't left something disconnected. Because I thought in my poor addled brain the last thing I did is what killed this thing. Did I mention the Rabbit hole? What's even worse is I can't get anything off the OBD2 port either, it seems to kill that stone dead too. Also the "magic key" won't latch in place, lots of bleeps though, some of them from the car... But a totally black dash but the radio still works. If I try and work the wipers they will move about 1/4 of the screen then stop until I press the start button again.

I even bought a new 12V battery for it just in case. It's not that.

I took the traction battery pack out, stripped it all down, cleaned the copper links, they were in a state so it was ready. Charged and discharged all the cells, recharged them, balanced them, finished up with 218V across the terminals before the relays and as far as I can tell a pretty healthy battery for an 18 year old Prius with 160,000 miles on it's odo.

It will run a 240V 60 watt light bulb more or less for about 12 hours, then I recharged it all again, I'm getting good at whizzing those 8mm nuts off I can tell you. I charged it with two decent quality "Hobby chargers" one cell pack at a time, they are all good.

So this is where I am. I put the Orange plug in and push it down.

I put the "magic key" in and push the brake pedal down and press the start button.

I get a dash full of the usual lights for about 1 second then the "FNRP" boxes all lose their writing and turn into boxes then it all goes black.

If I take my foot off the brake and hold the start button in for about 3 seconds the "Prius" screen will come to life, but none of the buttons on the touch screen work. At all. nada. And the graphic for the battery shows a white empty box.

So I have read up, watched Youtube videos all night, and all that I have gleaned from this research is that when the start button is pressed the Hybrid brain is supposed to send a signal to the Battery control "brain" to turn the relays on to test all the Orange cable work, and control circuits if it's all ok it allows the car to run as normal, if it finds anything wrong it seems to kill everything. Am I about right here?

Now the last major thing I had done was to have a new A/C compressor fitted and a regas/new condensor rad, the A/C worked wonderfull. So I think I maybe need to start from the battery, find the Hybrid brain, check every connection from there and see what I can find?

Or am I missing something stupidly obvious?


· Registered
3 Posts
Discussion Starter · #4 ·
1. Open the driver door with no fob in slot and the doors unlocked.
2. Insert old fob into slot and remove it twice within 5 seconds.
3. Close and open driver door twice.
4. Insert and remove old fob once.
5. Close and open driver door twice again.
6. Insert old fob in slot and close door.
7. Without pressing the brake, press power button, wait a second, press it again, wait a second, press it a third time to turn car back off.
8. Remove old fob from slot. You'll be in "add mode" at this point.
9. Car should lock and unlock doors twice to verify it is in add mode. (indiacting "mode 2")
10. Press and hold both buttons on OLD fob simultaneously for a second and a half. (door locks cycle)
11. Press and hold both buttons on NEW fob simultaneously for a second and a half. (door locks cycle)
11. WAIT 3 seconds, press just the lock button on new fob.
12. Car should respond with one quick lock/unlock to verify that the new fob is all set. This may take a moment or two.

13. To end this programming, open a door or put fob in the slot.

An interesting FYI... ALL FEATURES WORK. and When starting with the new fob, the hazards blink once before starting. I can live with that
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