02 Tacoma. Crank no start no spark

02 Tacoma 2.4l 4x2

no spark no fuel no engine light but cranks no communication with scan tool

daughter started truck ran like really bad she turned it off and now won’t start and engine light is off.

so engine light doesn’t turn on when key in on position.

running through the internet and here I have tested
fuel pump.
Replaced all battery cables (thinking bad cable)
It’s a 2 month old battery tested good
went ahead and replaced all fuses. Had a extra new starter relay and a EFI relay.
Crank and cam sensor replaced. Checked all grounds and connectors. Good.
Tested ignition good replaced about 1 year ago (broken key)
No spark but have voltage at clip
Pulled cover and trimming Chain is fine.
even looked at neutral safety switch

im thinking it might be the ECU

It has been a work truck Sense new basically every day. 292,000 miles

many help would be great before ordering new ECU

 

Welcome to TW Tyler

 

Need to check for power/ignition/ground to ECU.

If the check engine light isnt coming on, you're right its an ECU failure.

 

Bishop84 thank for the replay.

I have a print out chart of pin location but suck at reading these things Any clue what pin terminal I’m looking at.

also noticed it says Auto wire color L what color is L

 

There was a recent post of a guy with a similar issue. He found that the circuit board on his ECU was corroded to hell. I would check that personally.

Edit: here is the link.

https://www.tacomaworld.com/threads...rank-no-start-long-post.669264/#post-23486782

I know it’s a different motor/Ecu but consider that manufacturing these things, the protections for the board, placement are similar and from the same era.

 

L is blue, black is b

 

3 fuses to check Ign, OBD and EFI.

if the CEL in not iluminated that is telling you that the PCM is not "alive". I am not saying that it is bad, it just isnt getting any power. recheck those fuses mentioned then check for power and grounds at the PCM. if all readings are what they are suposed to be then the PCM is bad, rare but it does happen.

 

Sep1911
Already did that had a s10 do that some time ago. So I pulled ECU unscrewed it and gently pulled it apart with gloves on and looked at all of it and couldn’t see anything burnt but that doesn’t mean something is bad.

I’m going to do what glamisman Stated first later today then go from there

 

Ok so I need a hand I can’t seem to understand this electrical system have always been confusing to me. What is the power/ignition/ground to ECU color or even location any help thanks

 

So heres the manuals from an 03, hopefully they're close.

If I'm reading it right, each wire on there is labelled with an A, B, C or D. In the center of the bluish block, those letters correspond to a connector. You can see what the connector looks like in the conneto.pdf file. For example, the the Black-Yellow Battery wire is Pin 1 of connector A, which is E5 on page 3 of the connector guide.