2004 Toyota Prius no lights on after 12v battery replacement

A couple of years ago, I experienced similar problems with my 2009 Gen II. The SKS system started getting "flakey" and so I replaced the button-cells in the FOBs, but that didn't seem to fix it, so eventually had the dealer do a load test, and sure enough the 12V AuxBattery was dying (well, it was 6+ years old! ). I jumped the car with my trusty Power Pack (see threads passim) - but I had the dealer replace the 12V AuxBattery (the car needed to go in for a service anyway!) - and (just for completeness) here's a test which might be useful to you:
DO-IT-YOURSELF TEST PROCEDURE (thanks to jdenenberg):
- Without brake pedal, press the Power button once and release to enter ACC mode
- Press and hold the MFD Info button, then turn the lights on and off three times to enter Maintenance mode; release Info button
- Press “Menu” (on screen)
- Press “Display Check”
- Press “Vehicle Signal Check” - the battery voltage is shown and should be about 12.4 to 12.8 Volts (normal for an unloaded battery)
- Again without brake pedal, press Power button and release to put a current load on the battery - the voltage should stay above 12.0V (if less than 12.0V the battery is not well, or there is a fault or unusual load somewhere)
- Press brake pedal and press Power button once to enter "Ready" mode - the battery is now charging at about 14V (if less than 13.6V or more than 14.4 there may be a problem with the charging circuit)
- Turn car OFF to leave Maintenance mode

…and if you see any of the interior lights going dim, that's a sure sign the AuxBat is about to up-and-die!

- hope this helps - Wil

 

First things first.

Was the READY light on, when you tried starting the car? If it came on the dash, and didn't start, probably the HV battery pack must have experienced low voltages.

I don't think the video tutorial would be of any help, seeing that you already had power coming to the dashboard. Well, I don't know what sort of lights you saw, but if it did show the ready sign, and was a weak 12volt battery, replacing it with a new one would ha e solved the issue.

Was the new battery you installed new? Did you voltage test it under load or...to determine if it held some juice? If it doesn't hold, that tells y you didn't get any lights on the dashboard after replacing it.
Try checking the battery terminals connections to see if they're well connected.

There's also a fuse close to the positive battery post. If that fuse is blown, you might have no lights coming on on the dashboard.

If you ha e done all that, and its still same, could you please post a scanned results of any codes you might have of the car?



Dxta

 

No dome (overhead) light when you open the door? What happens when you switch on the lights (twist end of stalk on left of steering-wheel)? Not even a glimmer? Have you checked the fuses?

 

Some basic things to check:

1. Is the battery installed and connected with polarity correct. The negative post of the battery should be toward the back of the car.
2. Are the positive and negative cables connected firmly to the battery posts. I have seen the positive clamp installed incorrectly, where I could lift it off the post with no tools.
3. Is the negative cable bolted firmly to the body of the car (bolted to body closer to the back of the car toward the taillight.
4. Are the wires plugged into the positive terminal clamp assembly? There should be two push in connectors attached to the assembly.
5. Are you able to use a multi-meter to check the actual voltage of the new battery you just installed?

 

Let's start with the dome light.
Do you have power at the dome light?

 

Try getting a digital voltmeter to test the voltage of the battery. Or better still, remove the new battery, and instaethe old one and see what happens. If it brings lights on the dash, the new battery is dead maybe.

PS: If after replacing the old battery back in the car, and there's mo light on the dash, that means you have am open circuit problem on the 12V circuitry.


Dxta

 

Double check the voltage of the battery. Either do it yourself, or bring it back to where you got it and have them check it. (most stores will check it before selling it.)

If voltage is OK, then may need to start checking fuses.