Stupid cheap Chinese radio not working as advertised

[7milesout]

All Mirage have that feature, but don't expect it to perform miracles.

When the you take your foot off the gas while the car is moving and the engine revving above 2300rpm or higher, the alternator will put out the strongest current (amps) possible to the battery, regardless of the actual charge state of the battery.

foama - Do you 'reckon' the Merican cars do this too? And the manual transmission cars too? I can't say that I've noticed this on my 5 speed. However, on my 2003 GMC Sierra, with a 4.8L V8 and automagic transmission, if I go off-throttle for a long enough time, I can feel something (and hear it) that sounds like it could be doing this. When I go off throttle in that truck (no brakes applied), after about 3 or 4 seconds, not only do I feel a skosh bit more deceleration, but now with the Borla muffler, it goes into "popcorn" tune simultaneous to this slight braking feeling.

I was assuming that at this 3 or 4 second mark, the ECU was going to 0% gas input. And that's what I was feeling. However, now that I think about it, I don't think I'd be getting the exhaust popcorn sound unless the exhaust were rich. I wonder if this ole 2003 model truck is doing that alternator regen thing...

mohammad - He's not saying that this happens during braking. I'm not sure what DFCO means. He's saying it happens when off throttle.

foama - I'm not understanding how you think this alternator regen might be saving gas. My understanding that when off throttle on a manual, the ECU is programmed to fuel at 0%. And what I've seen on my OBD-II BT device and associated smartphone app, this seems to be true. This alternator regen would still work on a 5 speed, but shouldn't be saving any gas, as it is at 0% under these conditions. The CVT, as I understand, continues to fuel at some small % even off throttle. I don't see the alternator regen changing that either. Maybe there's something else that leads to fuel saving that you haven't mentioned yet? -- Caveat -- I don't know the ECU fuels like I mentioned above, that is only my understanding.


- 7milesout

[foama]

this happens during braking. I'm not sure what DFCO means. He's saying it happens when off throttle.

I'm not understanding how you think this alternator regen might be saving gas.

I don't drive a CVT model, but ECU and alternator are similar except for what the CVT needs.

Yes, being off the gas with an engine revving higher than about 2300rpm cuts off the fuel into the engine.

During the regen braking, the alternator loads (or brakes) the engine a bit and consequently puts out as much as it can into the battery. At a later time, the thereby excessively charged battery has less need of being charged, so the lack of loading the engine by powering a charging alternator saves us fuel.

[mohammad]

mohammad - He's not saying that this happens during braking. I'm not sure what DFCO means. He's saying it happens when off throttle.

I doubt we have regen braking, if I somehow decide I have an extra $400 USD burning a hole in my pocket i will buy an oscilloscope and make a youtube video testing this out and ill let you know what the results are.

DFCO is deceleration fuel cutoff its exactly as you described 0% fuel going to the engine causing you to slow down. Your transmission may also possibly be shifting into neutral to save gas as the mirage does. But it probably isnt doing that while in motion.

CVT should not be using fuel when off the throttle. You do bring up an interesting point, since the cvt pump is needed to change ratios and what have you. The auto stop and go mirage has an electric CVT fluid pump it runs when the engine is shutoff.

Foama already answered your question about how regen braking increases efficiency. Regen braking is the ONLY benefit that hybrid cars have over the auto stop and go mirage. Although a hybrid normally shuts off the engine while Rgen braking so thats also a small difference. This free energy while braking is so magical, some cars like BMW will run the AC compressor while braking to cool the cabin for FREE.

[7milesout]

Foama already answered your question about how regen braking increases efficiency.

No. Not regen braking. Regen alternating!

I can imagine the regen alternating working as described. But I can't imagine there being a time after regen alternating when cruising along that the alternator would put out either nothing or close to nothing, to the point there is little to no load from the alternator. But I suppose it's as possible as the regen alternating. However, even if it did the no-alternator-load cruising, I can't imagine there being much fuel saving. But whatever small fuel saving there is, I'll take it. Tis a cool discussion.

[mohammad]

No. Not regen braking. Regen alternating!

I can imagine the regen alternating working as described. But I can't imagine there being a time after regen alternating when cruising along that the alternator would put out either nothing or close to nothing, to the point there is little to no load from the alternator.

If the alternator say put out 15v(a random example number) while regen braking then when the alternator resumed normal operation it would have ZERO load until the battery voltage dropped to 14.4 volts. This is mentioned in the photo in post #51 found here: https://mirageforum.com/forum/showth...ll=1#post75549

They also discuss fuel savings on that thread, its quite substantial I believe its something like 3-7% during the time the alternator is not in use.

[mohammad]

UPDATE ON THE RADIO ISSUE: I believe maybe the issue is that the "illumination circuit" is receiving power when i hit the brakes. This is the circuit that powers the parking lights and the backlight on gage cluster and buttons in the car. I think maybe a brake light has shorted the 5w and 21w filaments. So when the brake lights turn on the illumination circuit receives power and the radio thinking my parking lights are on dims its screen.

I have come to this hypothesis because one time i hit the brakes the buttons on the side of the radio lit up for a split second like i had turned on my parking lights.

This unfortunately does not explain why this issue primarily occurs when the car is in motion and rarely occurs while the car is stationary.

Seems like a real pain in the ass to hookup a multimeter to test my hypothesis as how would i look at the meter while driving as im too cheap/poor to buy a meter with logging capability.

I may just change the brake lights to test my theory

[Fummins]

UPDATE ON THE RADIO ISSUE: I believe maybe the issue is that the "illumination circuit" is receiving power when i hit the brakes. This is the circuit that powers the parking lights and the backlight on gage cluster and buttons in the car. I think maybe a brake light has shorted the 5w and 21w filaments. So when the brake lights turn on the illumination circuit receives power and the radio thinking my parking lights are on dims its screen.

I have come to this hypothesis because one time i hit the brakes the buttons on the side of the radio lit up for a split second like i had turned on my parking lights.

This unfortunately does not explain why this issue primarily occurs when the car is in motion and rarely occurs while the car is stationary.

Seems like a real pain in the ass to hookup a multimeter to test my hypothesis as how would i look at the meter while driving as im too cheap/poor to buy a meter with logging capability.

I may just change the brake lights to test my theory

You could just remove or unplug both brake/tail light bulbs to see if that "fixes" it?

[mohammad]

You could just remove or unplug both brake/tail light bulbs to see if that "fixes" it?

The problem only consistently occurs when the car is moving and the brakes are applied. So that would be a scary idea to test.

[inuvik]

The problem only consistently occurs when the car is moving and the brakes are applied. So that would be a scary idea to test.

There is always a large mall / superstore parking lot you could try this and not be on the road.

[Fummins]

Besides, there's a big led brake light at the top of the hatch. The only thing I'd be concerned about would be throwing abs/traction control codes and having the thing lose throttle response...The neat things that can happen when both brake lights burn out on these cars.