Check engine light NOT coming on!! Emissions failed! Help!

Why so it is; thanks for looking that up.

Turns out those are two different sections: ES-435 is where the "MIL circuit" troubleshooting starts.

ES-427 is a page in the middle of troubleshooting for the "VC circuit" that starts on ES-425. VC is a 5-volt reference generated by the ECM and relied on by the throttle position sensor, canister pump module, water valve, and fuel tank pressure sensor, as shown in the circuit diagram on ES-426. You would only get here from the main "MIL circuit" troubleshooting steps if sent here from step 5B on page ES-438, which would be if the MIL never comes on and the engine doesn't start (and a scan tool can't hail the ECM). I don't think that's the story here.

(Now, for anybody who has a MIL never lights and engine won't start and scanner can't connect story, then yes, step 5B would send you to the VC circuit diagnosis, which looks like it is checking for the chance that a short in one of those four sensors is pulling VC down. All of this goes to show why it's so important to look up the troubleshooting steps in the manual; they will often cover possibilities you wouldn't just think of offhand.)

So with the engine starting, I think you'd end up next on step 6, to inspect the combination meter (following the steps on page ME-11), or checking out the wiring between the meter and the ECM (using the info in the wiring diagram).

That's a funny thing that happens weirdly often on PriusChat: you'll post a question, get kind of a first wave of pretty on-point responses, then a little lull, then a kind of second wave of people who don't even bother reading the earlier info about whether there even are bulbs or they're LEDs, and kind of drop spammy suggestions into the thread. Life on a forum, I guess.

There is information here on how to access the circuit board with that bulb LED on it, in the drawing attached in post #9. The circuit board is shown there as 83247B.

To get there, you need the top of the instrument panel off, following the instructions in the repair manual (more info). There probably are threads or youtubes that cover that operation, if you get the right magic words in your search phrase.

Because electrical troubleshooting is detail-oriented and tedious, and disassembling the instrument panel is quite tedious, and this issue features both, if you have choices of a shop that bills $80 an hour and one that bills $160 (assuming they're both up to the job), that'll add up fast as the hours go by.

Parts, if it ends up being that meter circuit plate no. 2, it's either $33 or $84 MSRP depending on which one your car has. If it's the ECM, that's $800 MSRP. If it's the instrument panel wire harness, that lists for $3900 to $4650 depending on which version your car has, plus the labor of total instrument panel disassembly to replace it. Usually, of course, a shop will just locate where a fault is and fix it rather than replacing the whole harness, but sometimes a dealer might try to push replacement rather than tasking their techs with a tricky diagnosis.

Sometimes there are things you can do to reduce the shop's labor when it's such a big part of the job. There was at least one time I drove a car to the shop with most of the instrument panel and carpet removed, just the steering wheel and driver's seat put back in, so they wouldn't spend time on that stuff.

There's also always the chance with something like this that it turns out to be fixable with $0 in parts once the issue is found. Then it's just the labor.

 

The dealer's going to tell you they can't fix it either so you better get ready to just take it apart and see what you see because it won't take any time to get to a pillars apart and get the piece out if you had a spare maybe but you're going in kind of blind here thinking that the LED is burned out so you have to get to the LED and apply power to it to see if it will power

SM-A715F ?

 

As ChapmanF pointed out, the MIL is a LED that's on a circuit board with a bunch of other LED indicators- the LED itself could fail but that's really rare. There is no "set price" for diagnostics. It takes what it takes, at xx dollars per hour. Maybe they find the fault in the first hour, maybe it takes 4 hours (or more).

The MIL has a dedicated power feed (from the IGN fuse) and ground control direct to the ECM. If I looked at something like this, I would make a 12V "test LED" to mimic the MIL, then check the MIL control circuit at the ECM behind the glove box. If that worked, then I would remove the dashboard trim panel for the power button and test the IGN and MIL control circuits at the inline connectors (IG1 and IG2) for the combo meter. That would direct me to whether I had to test directly at the combo meter or not.

 

The problem intrinsically is probably quite cheap and worthwhile to fix.

If your only option for fixing it is to pay somebody else $160 an hour for as many hours as they take to fix it, then that can change the calculation by a lot.

 

First things to consider is where you located You obviously have an emissions test or an OBD test so something say on the east coast Tennessee Georgia North and South Carolina places like that it's pretty easy to get a rider and just keep driving the car so location has a lot to do with it what you can do legally in your locale well many times determine the output of what you do here where I live in the southeast I can pretty much do what I want I live in the county with no emissions just a safety inspection

SM-A715F ?

 

Careful with that. For a free LED it would need to be tested with a drop resistor to limit the current to 10mA or whatever it is rated at. If you just hook it up to 12V (or probably even 5V) it will likely fry from the test. If it is on a circuit board applying a voltage to it could conceivably blow up some other component.

Has anybody got a picture of this board (not the drawing from the manual)? "Back in the day" all these indicators were little bulbs and you could just twist them out and replace them. Are the LEDs in the Prius socketed, through hole, or surface mounted? The first one is easy, the second would need a soldering iron and a sucker or some wick, the third one you would need a hot air workstation (also really good up close eyesight or a microscope, as surface mount components are usually tiny.)

 

Stand by a pic will be coming if I can post just had it. The whole board apart and a 05 and 09 side by side just for hale of it

SM-A715F ?

 

Not socketed. Lil wires soldered to ice board I had this thing out checking every wire. And solder joint

SM-A715F ?

 

"Worth" is a funny concept that is very different for many people. How much would you get in trade-in for a "broken" car and how much more would you pay to buy a newer car- assuming that there is something available.

Maybe it costs very little to fix your problem and you get another 50k. Maybe you have to spend many hundreds $$ and then the HV battery goes, or the cat is stolen, or whatever.

It all comes down to YOUR risk tolerance and financial situation.

Posted via the PriusChat mobile app.

 

I don't see any pix.

In the next message you said "little wires soldered to board". That doesn't sound like surface mount, which is good, because then the OP can probably fix it. Do the wires go straight down from a rounded clear (or colored) plastic package, through round solder filled holes, with the leads clipped close to the board on the other side? If so it should be easy enough to fix if the problem is only the LED. Just desolder those two holes, pull out the old one, put in a new one. (It would help to know what the current rating is though.) If it is assembled like that one could also tack on little wires to the solder joints to measure the voltage across the device. If it is blown it would probably be 5V or 12V across it, if it is working it would be close to 0.7V when it is on, 0.0V when it is off. Or just replace the whole board, which somebody posted above wasn't too expensive.

 

hello, i had the same issue engine light not showing,did you get that fixed?

 

For some reason I can't post pics here but yes it was a soldered board The board where the capacitors that the Florida people replace it's a whole assembly with the display and all soldered to it I still have the pictures I can send them directly can't make them happen they need to be resized and fooled with and whatever but I could probably solder the capacitors on here I believe that's what they're called and I don't do any soldering at all I wouldn't personally risk it I have a buddy of mine do it but it's not completely machine done I don't think or if it is it is workable I've seen more complicated boards be fixed on other things that I service for a living so this shouldn't be a huge to do A dude down in Texas has made it a side business at his shop

SM-A715F ?

 

As Tombukt2 mentioned - it might be a good idea to look into getting a waiver and it appears your State does offer such a waiver under certain circumstances. You might need to pay for a diagnostic report and get a quote from your local dealer, but I'd think you could qualify for such a waiver. It would buy you another year to address the problem.

AZ Waivers