wont start, please help

[Aspec]

i'll replace the fuel tomorrow, all the fuses are good. im tryin to schedule w/ a local to try my ECU on his running car and his ECU on my car.

Please do not go swapping ECU's before you check out that circuit! You run the risk of frying your buddies as well and then your totally hosed! A short in the harness could have fried it. Don't skip steps in the diagnostic process. You will be happier down the road.

 

[kotu100]

would you mind letting me know how to test the DAIG circuit. i've been looking for something in the TSRM for it but i couldnt come up w/ anything.

 

[jetjock]

http://tinyurl.com/52y64e

You could also check for the presence of codes by using Vf.

 

[Aspec]

would you mind letting me know how to test the DAIG circuit. i've been looking for something in the TSRM for it but i couldnt come up w/ anything.

Yep. Here's the link from post #9. http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=FI&P=29

And I think JetJock just posted it up as well.

 

[Aspec]

Okay. From the "S" connector side of the ecu, the TE1 terminal is #15 on the connector.

http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=48


The TSRM shows it should have 4-6 volts at that terminal with the ignition on and NO jumper between TE1 and E1.


http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=50


From the "R" connector the E1 terminal is #14 and goes to ground location "B"


http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=47


Speaking of grounds... Do you know where they all are and have you checked them?

http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=149

http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=151

 

[suprahooked]

Dude try new spark plugs, It happen to me and new plugs were soaked so i put new ones in and it fired up. $12.00

 

[kotu100]

it got brand new plugs when i did the rebuild.

ill check the ECU in a bit and let you guys know...

 

[Aspec]

it got brand new plugs when i did the rebuild.

ill check the ECU in a bit and let you guys know...

What he's telling you is even new plugs can get washed down and fouled with fuel. At least pull them out and make sure they are clean and dry.

 

[kotu100]

i did that... nothing. still tryin to check the diag. circuit, bein a pain in the ass. the connectors on the ecu do NOT have the lil flap to expose the wires.




well i cant find the black/green wire (W) on the ecu plugs. what year is the TSRM diagram for? i dont understand how the same diagram is used for 2 different wiring systems.

 

[Aspec]

i did that... nothing. still tryin to check the diag. circuit, bein a pain in the ass. the connectors on the ecu do NOT have the lil flap to expose the wires.

well i cant find the black/green wire (W) on the ecu plugs. what year is the TSRM diagram for? i dont understand how the same diagram is used for 2 different wiring systems.

wtf? Do not use the picture above the diagnostic tree if thats what you are talking about. I gave you links to the actual wiring diagrams along with the listing of which plug and contact number. Start by checking for continuity from diag terminal E1 to ground. Then check the grounds at ground location "B" under the intake manifold and if needed we'll go on from there.

Okay. From the "S" connector side of the ecu, the TE1 terminal is #15 on the connector.

http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=48


The TSRM shows it should have 4-6 volts at that terminal with the ignition on and NO jumper between TE1 and E1.


http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=50


Fron the "R" connector the E1 terminal is #14 and goes to ground location "B"


http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=47


Speaking of grounds... Do you know where they all are and have you checked them?

http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=149

http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=151

 

[kotu100]

all the grounds in the engine bay are good. i tried jumping E1 and TE1 at the ecu but the CEL still didnt blink. so im almost 100% positive i have a bad ECU. hopefully ill get to test it on a running car today to confirm.


i was lookin at the links you gave, but how do i know which pin the wire is without having a diagram showing the plugs... unless i just go by wire color.

i appreciate all the help, thanks a lot aspec

 

[Aspec]

all the grounds in the engine bay are good. i tried jumping E1 and TE1 at the ecu but the CEL still didnt blink. so im almost 100% positive i have a bad ECU. hopefully ill get to test it on a running car today to confirm.


i was lookin at the links you gave, but how do i know which pin the wire is without having a diagram showing the plugs... unless i just go by wire color.

Connectors R, S and T.

http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=52

There are actual numbers on the connectors but they are so small you can go blind trying to see them.



Did you have continuity between the E1 terminal on the diagnostic connector and ground? (negative batt terminal or block will do)

Check for continuity between E1 on the "R" connector at the ECM and ground location "B".

Check for continuity between E1 on the "R" connector at the ECM and the E1 terminal at the diagnostic connector.

The results of these checks will determine your next step.

i appreciate all the help, thanks a lot aspec

You are very welcome.

 

[kotu100]

Connectors R, S and T.

http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=52

There are actual numbers on the connectors but they are so small you can go blind trying to see them.



Did you have continuity between the E1 terminal on the diagnostic connector and ground? (negative batt terminal or block will do)

Check for continuity between E1 on the "R" connector at the ECM and ground location "B".

Check for continuity between E1 on the "R" connector at the ECM and the E1 terminal at the diagnostic connector.

The results of these checks will determine your next step.




You are very welcome.

well i DO have continuity between E1 and TE1 so im stumped....
ill check everything else later.

 

[Aspec]

all the grounds in the engine bay are good. i tried jumping E1 and TE1 at the ecu but the CEL still didnt blink.

Sorry, I read through that so fast it didn't sink in - trying to jump TE1 and E1 at the ECM won't work if E1 isn't grounded - chk E1 like I suggested. :icon_bigg

well i DO have continuity between E1 and TE1 so im stumped....
ill check everything else later.

Checking continuity between TE1 and E1 was not on today's menu - stop confusing yourself. :icon_bigg

 

[Aspec]

well i DO have continuity between E1 and TE1 so im stumped.

Hmmm...

Just out of curiosity where did you check that from and was the diagnostic connector jumpered when you did it?

 

[kotu100]

i just used the multimeter probes as if i was jumping it.

i tried grounding out E1 at the ecu and it showed no continuity. ill try again tomorow just in case.

 

[Aspec]

i just used the multimeter probes as if i was jumping it.

i tried grounding out E1 at the ecu and it showed no continuity. ill try again tomorow just in case.

Um ya. I'm guessing you still have the battery hooked up. You are going to want to disconnect the positive battery terminal.

And I'm assuming you still have the ECM plugged in to the harness so the reason you have continuity on the diag port is you completed the circuit. So that means you had voltage coming out of the ECM and the E1 diag terminal has ground.

That takes us back to... unplug the "R" connecter from the ECM and make sure E1 (terminal #14) is grounded, preferably to ground location "B" under the intake manifold. (there should be a cluster of ground wires bolted to the intake under the plenum)

 

[kotu100]

so i went ahead and put the other ECU in (yea yea i know....) and i have a code 51. YAY!!! :3d_frown:
so ill be checkin out the CPS a lil later today. any tips?

 

[Aspec]

so i went ahead and put the other ECU in (yea yea i know....) and i have a code 51. YAY!!! :3d_frown:
so ill be checkin out the CPS a lil later today. any tips?

Um..... No.:nono:

Code 51 is not a CPS code. Code 51 usually means the throttle was opened (gas pedal pressed) while the ECM diagnostic terminals are jumpered.

Did it start with the known good ecm?

 

[gtsfirefighter]

Did it start with the known good ecm?

Exactly! Inquiring minds want to know. How could you leave out that detail?