97 tacoma 3.4 crank no start after tps replacement

All we really have left to do is check the grounds to the ECM.

Before that, check the 10a Gauge fuse.

Then you need to move on to the ECM ground.
But lets use the ECM power to test the grounds.

Something odd is going on here.

First undo the E5, E6 and E8 connectors of the ECM.
Go from Pin 2 (black/yellow) of the E5 connector to the E8 connector pins 13, 24, and 26. (all brown wires)
Do the same for E6 pin 7. (brown wire also)

E5-2 to E6-7 (Brown)

E5-2 to E8-13 (Brown)
E5-2 to E8-24 (Brown)
E5-2 to E8-26 (Brown)


We want to see 12v on all these readings.
Key On

 

the first on your list (E5-2 to E6-7) is the only one that did not read any voltage. the last three all read 12 volts. gauge fuse is good

 

That would mean the ground is not good on that wire. So that’s a start in the right direction.

we are getting somewhere.
Hang tight man. Let me look at the diagrams and wire routing.

I am also in the middle of helping my nephew look for a car. He’s about to be 16. And you know how that is, no patience. lol

My phone has been busy all day.

 

no rush at all you are saving me so much work and potentially messing more stuff up thank you so much you are awesome. congratulations to your nephew.

 

The bad news is, we still need to figure out why the fuses keep blowing.
But we need to address that ground wire first. The ECM isn’t going to come back on line until it’s fixed.

 

Just to confirm, E6-7 was a brown wire, correct?

 

There is a possibility that the E6-2 is shorted to power.
Check E6-7 from that pin to body ground. Like a bolt or something under the dash.
See if it still says 0v.

 

Better yet, go fro E6-7 to E8-13.
See what you get…

 

i tried E6-7 to E8-13 and also E6-7 to a solid ground and got 0volts. now, i used the mode on the meter where itll beep when the test leads touch, and it beeped when E6-7 to solid ground.

 

That is odd.
Are you sure you had a good connection on E5-2 when you checked E6-7?

If you have continuity (beep mode) between E6-7 and Body Geound.
Then you should have shown power (12v) when you checked E5-2 to E6-7.

Maybe check again. Something is off here……

 

i apologize, yes there is 12 volts from E5-2 to E6-7. im sorry

 

Ok. No big deal.
That is good.

But now we are back to square one. At least for now.
BUT....We know the powers and grounds are good.

Let me dig a bit deeper.

 

Also, why did you change the TPS?
Was there a problem with it?

 

ive replaced almost all sensors and or cleaned them. tps was my last one to replace. ive been having a fuel air problem, couldnt hold 70 on the highway and the motor would be very jumping at certain rpms.

 

What lights are these?

Also, what happens if you turn the key on and press the throttle wide open, and let off?
Do that a few times, see if the fuse blows?

There's not but one more power wire to the engine controls that we haven't checked.
And it doesn't go the the ECM directly.

All we have left is the 5v ref. And I can't see that causing your issue.

 

just all the dash lights that come one when the key is in the on position, usually they all light up before starting including check engine light but there is no check engine light. im out of town for work this week and will get back to you on that this friday again thank you for your help.

 

I keep researching.
I will be in and out over the weekend.

If the weather is clear here, I'll have to catch up on some work over the weekend.
But I'll check in.

 

good evening, no fuse was blown with throttle pressed down.

 

I mean we have checked all the powers and grounds to ECM.
And we tested all the powers and grounds to the DLC (OBD port)

The ECM just isn't responsive.
I'm always hesitant to call it an ECM.
But all the powers and grounds are there (for now).

My biggest issue is, what is blowing the fuse?
And what happens if you put a new ECM in and this happens again?

I'd wiggle, jiggle, move and tug on all the wires going into and out of the engine harness and ECM.
Try hard to get that fuse to blow. I suppose it could be the ECM blowing it. But I highly doubt it.

Then I inspect the pins of the ECM connectors and make sure they all look like they are making good contact.

Then, it's your call.....
Do you throw an ECM at it.

Also, see if your scan tool will connect to a different vehicle. Just to make sure it's "good".
(Pretty sure it will. But let's just see)

 

good afternoon, i put a new computer in it and it did not fix it. what else is there left to check?