Yeah yeah... voltage check, etc etc but I don't have a multimeter, little brother stuck it in the wall socket incorrectly and popped the whole damn thing.

So I tried to calibrate it using the LED method.

I JUST got this TPS from KNONFS... and he's got quite a few posts... so I would hope he didn't **** me over and sell me a crappy TPS.

I will measure ohm sweep ASAP, but don't have time to get a multimeter.

Well... the vid speaks for itself.

I tried turning the set screw every which away, and the LEDs never lit, so I took off the narrow range and pressed it in by hand, to see when/if it would light up. One LED will barely flash once the rod is pressed in all the way, and when I let go it flashes.

I would think the TPS is good, seing as how when I push it in all the way, I can hear the releif solenoid clicking. It operates fine (as shown in the vid)

Also, with my AFC... I'm pretty sure I have the TPS type set correctly... but it registers 100 percent and 4.8+V... the same reading I get when I was driving without a TPS.

I have reset the ECU. 3 times. I unplugged the ground, hooked up the TPS, waited 30 secs, then connected ground. Did the same thing. Left TPS hooked up, disconnected again, then did it all over. Same deal.

When I press the rod for the fullrange (sensor on top) then I hear other relays/solenoids or whatever clicking as well.

What do you think? I was sold a dud?

www.aztechrotary.com/perla/tps_led.wmv
(1.3MB)

 

Dude, if you don't have your complete emissions setup, the LED test might not work right. This is due to the fact the the light method ties in to the port air and split air solenoids' circuits. Mazda wanted idle conditions at the point one is energized, and the other isn't. Without the solenoids hooked up electrically, the ECU can't "drop" the ground on them to complete the circuit, hence no LED power...

Multimeters are like $10 at Radio Shack, and with this car, you know you're gonna need it again (soon, lol), so break down (no pun intended) and get one

 

heh.. well the switch and relief are plugged in... just not the split air or port air solenoids. EDIT; just noticed you pointed out the split air and port air.

Well damn... oh well.

Well, this means my AFC wiring is ALL fucked up then No matter what its reading 100 percent. The arrow should be pointing up to the right correct?

I'm still trying to figure out why the voltage check shows two AFM's hooked up (to IN numbers...)

 

Oh hey, I meant switching and relief, lol. Heck, I need to go get the scematics now, before I screw you up more, lol. Sorry. Split air is the animal down on the ACV...

So, in any case, if your solenoid rack and rat's nest is still intact (that's a rarity, lol), then the LED test should be working. In fact, you'll hear the solenoids kicking in as the lights come on & go out. I did this test once, a long time ago, before I figured out that you can get a much more accurate reading while checking it at the ECU and adjusting your 1 volt there...

EDIT: Yep, relief (blue) and switching (grey) solenoids...

 

The LED method will work with or without the Vac Rack installed.

 

When you clip an Ohmmeter on the TPS it should sweep from near 0 to around 5K.
Here is a short vid of a worn out TPS.
TPS test

 

I wouldn't trust adjusting it anywhere near the engine side of the harness. I tried that a couple of times, and my idle was getting so bad that it would start to randomly die at stop signs.

I took Wayne88's advice and it fixed the problem pronto.

 

The LED's should work fine withuot the solenoids plugged in. All you're doing when you connect the LED's is putting an LED in parallel with each of the switching and relief solenoids. Since they're in parallel, removing the solenoid should not efect the operation of the LED's. They'll still indicate when the ECU is switching the respective ground to activate the solenoid.

Not that I'm advocating the use of LED's for checking the TPS. DMM is best.

 

One item you must keep in mind is that if you going to do the light method, the tps must be set at 1k ohms or 1 volt as a starting point.

 

Actually, the way I ended up setting my TPS was a combination of all 3 methods. Started by using the twin LED method to get a single lamp lit. I bought two LEDs and some spade lug connectors at Radio Shack for about $6. Once I get that, then I verify with resistance and voltage readings, tweaking it as I go. Then go back and verify that only a single lamp gets lit. Maybe some extra trouble, but not that time consuming, and worth the effort IMHO.

 

All right NZ and Rat, look at the schematics on page 50-31, and let's go over this...

Remember that the upper check connector wire (on the schematic) will be positive, or a 12v potential, and the bottom two wires will be the "negative" side of things. Now, take the solenoids out of the picture, mentally, or with white-out, if you prefer, lol...

You'll still have a complete circuit by shoving an LED into either circuit via the check connector (your parallel circuit theory, NZ), as long as the ECU is giving whichever "solenoid" a ground, but without the normal impedance of an energized solenoid there, you're probably going to fry something in the poor little ECU. In other words, instead of voltage dropping across a solenoid AND the LED (which is what the internal circuit was designed for), you're shoving voltage across a puny LED and straight to ground through the ECU. Mucho current flow...

Make any sense? So yeah, the LED's will work, but as far as I'm concerned, you can do that test without the solenoids on your car, but I'm not doing it on mine

 

I'd like to suggest that one of the drivers or whatever they are in the ECU that put a GROUND on the green check connectors two *eyes*, is......KAPUT. As in someone at sometime MIGHT have used a light that put to large a load on *the device* and burnt that sucker out.

Yes, I know both *eyes* on the green check connector are spliced to the Switching and Relief solenoids. How about this: if you have the engine hot and idling, when you pull the elec plug off the relief solenoid....does it click??? As when you put it on then off, do you feel a clicking of the Relief solenoid???? That would at least tell you if that part of the circuit is good or not (one of the eyes). Someone else will have to tell you how to check the Switching since its not grounded at idle.

By eyes in talking about the green check connector I mean the two sockets that are side by side. They get a ground from the ECU at given times. The mouth is the single socket and should have 12v anytime the key is to on. It's the grounds on the two eyes that turn the LEDs on and off. But you know that. That was for someone who hadn't thought about it. Enough. I gotta go look at my cruise control post now (fun)

 

Moral of the story for all of you guys that are confused by the many different test procedures given here- there is a chance you could damage the switching and/or relief solenoid valves' circuits doing the test with the lights, as Hailers alluded to in the previous post. You fry those suckers, good luck on the emissions test...

Everyone that posted in this thread is right, you can perform the check with LEDs with the rat's nest gone, although I highly discourage it. If the ECU is already fried for those circuits, the test isn't going to work anyway, even if the TPS is perfectly adjusted...

You can check the resistance sweep per Bill's post. I don't do that because this check only tests the TPS itself, not the circuit to the ECU...Personal choice...

And you can play with the solenoid plugs and listen for clicking (Hailers likes to play with things, I can tell ), whatever floats your boat...

And thanks for the vote of confidence, uRizen

 

Anytime, you sure the hell know alot more then me, and your method fixed all my idle woes.

 

Ok

TPS adjusted to 1Kohm at the plug (FOR NOW WAYNE!!!)

Just for ***** and giggles, started it up... idled at about 300 rpm.. BETTER THAN 2900!!!! but then quickly died.

So I have the ECU plugs un-done, and looking at the AFC wiring... I think I REALLY fucked it up. The only way the ECU would read less than 100 percent throttle is if I unplugged the friggin middle plug of the ECU.

So now I'm going over all the wires and such.. downloading the Apexi wiring manual again as we speak.

Wish me luck

TPS had a good sweep though...

 

That video is wrong. The TPS should be at 5000 +/-1000 ohms with the plunger fully extended.
If the TPS reads zero like he suggests, then its faulty.