Throttle Body Harness Read Out

GCPhotographers

GCPhotographers

Greenie N00B Member
Greenie Member
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Can someone confirm the voltage and ground reading for the throttle body harness pins.
I saw something as follows:
  • VIOLET (V): 5V
  • BLUE (L): 12V
  • SKY BLUE (SB): 5V
  • PINK (P): GND
  • BROWN (BR):
  • LIGHT GREEN (LG):
 
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Update: I still have to P050A and P050B and turning over sluggish. I broke it down and I am trying to run different test. Does anyone know what should be the read out for the 6 pin harness female side and then male side? The P050A appears before start up then P050B with it when turn over. I am trying to see if the TB is bad or PCM.

  • High or low engine RPM level (low RPM)
  • Engine may stall at idle (when I turn on the AC, it stalls)
  • The accelerator pedal may have to be depressed for the engine to start (not my situation)
  • Unusual tapping or popping noise from IAC motor (not in my situation but the car sound like it is running on 2 cylinders even though power is going through all four coil packs)
Google Causes:
  • Clogged air filter (This is not a factor)
  • Defective or dirty IAC valve (it is clean. I am trying to properly check the functionality as I can't find anything for 6 pins)
  • Vacuum leak (no leaks....checked in multiple locations)
  • Open or shorted circuits or connectors (this can be possible and I will share why but I can't confirm how much power the harness is supposed to receiving)
  • Defective electronic coolant temperature (ECT) sensor (I highly doubt this but I changed this a few months ago)
  • PCM Malfunction (I hope not)
  • Low battery voltage (When the car is turned over, the battery is draining fast...new yellow battery...when I disconnect the battery , the car dies)
  • Defective CKP or CMP sensor (I checked these and they seem good...multi-meter checked)
  • Engine temperature sensor issues (What else would I be looking for)
What did I do last: I replaced the MAC EBCS because it was leaking and cut the extended harness that was on the old one and add it to the new one since "Mazdaspeed Wire Tuck" was out of business. Any help with a solution would be great.

Just before that: Replace OCV and added my old OCV extension harness from "Mazdaspeed Wire Tuck"
 
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I did a parasitic battery drain test and the only fuse with an issue was the Room 15A fuse but this isn't a cause of those 2 error codes.
 
Voltage test in female pin with cable on negative terminal (11.6V) order left to right....pin:
  1. no reading
  2. 6.1V
  3. no reading
  4. 6.9V
  5. 6.3V
  6. 6.3V
 
Right now, I am looking at the throttle body, bcm, and maybe the alternator but why am I getting only around 7.1 to 8.3 volts at the attached image....all 8. Is the normal reading supported to be 12 volts?
 

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I'm pretty sure those fuses are all supposed to be reading battery voltage.

I'm not 100% on the read out at the TB plug off the top of my head. But can get you the answer.

As much as I don't want to admit this, as I am having issues of my own, but I'd wager by what you have already provided that it's either a harness or an ECU.

Do you have the shop manuals downloaded?

Specifically the wiring manual?

I can dig into all this but won't be able to till after this weekend as I'm about to leave town.

Sorry I can't be more help at this exact moment.

Edit: can you be more specific as to exactly what is going on?
 
Rokusek said:
I'm pretty sure those fuses are all supposed to be reading battery voltage.

I'm not 100% on the read out at the TB plug off the top of my head. But can get you the answer.

As much as I don't want to admit this, as I am having issues of my own, but I'd wager by what you have already provided that it's either a harness or an ECU.

Do you have the shop manuals downloaded?

Specifically the wiring manual?

I can dig into all this but won't be able to till after this weekend as I'm about to leave town.

Sorry I can't be more help at this exact moment.

Edit: can you be more specific as to exactly what is going on?
Click to expand...
I do have the wire diagram and I have been working in that area as much as possible. I am guess a sudden short because the TB harness reading is off as you know it is on the emission harness. I hope it is not the ECU but if it is, I have to looking a clone company etc.

I will be patient for your review as it will help with a solution. I am almost tempted to ship my car to someone to get it back.
 
GCPhotographers said:
I do have the wire diagram and I have been working in that area as much as possible. I am guess a sudden short because the TB harness reading is off as you know it is on the emission harness. I hope it is not the ECU but if it is, I have to looking a clone company etc.

I will be patient for your review as it will help with a solution. I am almost tempted to ship my car to someone to get it back.
Click to expand...

What exactly is happening?
 
I have a P050A before turning over and a P050B when turned over. No other codes. The cars sounds like it struggling to stay on. When the AC is turned on, car dies. When you take the battery terminal off, car dies. Last thing I did was swap the MAC EBCS because the previous was leaking. I have a log or 2 of the issues as well as video. When at full throttle, TB flap barely opens. I believe because of the lack of power going to it.
 
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Rokusek said:
I'm pretty sure those fuses are all supposed to be reading battery voltage.

I'm not 100% on the read out at the TB plug off the top of my head. But can get you the answer.

As much as I don't want to admit this, as I am having issues of my own, but I'd wager by what you have already provided that it's either a harness or an ECU.

Do you have the shop manuals downloaded?

Specifically the wiring manual?

I can dig into all this but won't be able to till after this weekend as I'm about to leave town.

Sorry I can't be more help at this exact moment.

Edit: can you be more specific as to exactly what is going on?
Click to expand...
How was the trip?
 
GCPhotographers said:
How was the trip?
Click to expand...

It went well, celebrated my wife and my 9th anniversary. Still getting things situated since we got back. About to head to bed then work tomorrow. I'll jump on the desktop tomorrow after work and dig into this more.

Do you have all the shop manuals downloaded or just the wiring diagram?
 
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What was the very last thing you did right before this happened? Is it possible the car is in limp mode based on the fact you are only running on two cylinders?
 
Rokusek said:
What was the very last thing you did right before this happened? Is it possible the car is in limp mode based on the fact you are only running on two cylinders?
Click to expand...
I did the EBCS swap because it was leaking and then re-wire of the OCV harness
 
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