No power to cam or crank sensor. Help please!

Can someone help me out here. Put back together my 97 2.7 3rz after changing head gasket and timing chain. Truck turns over but it’s getting no spark or no power to the cam or crank sensor. Coil packs are getting power. Truck is in fact in time correctly

 

Trying to check all the grounds. Any idea where all the grounds are? I know the one in the back of the head on passenger side. One by battery. One on the front of the lower intake manifold. Also the one on the coil pack bracket

 

Things were fine before you took things apart .

You have checked for any open fuses ??

Just what if any codes are you getting ??

Just how long did things sit apart?

Poor connection plugging something back together A pin bent can cause all kinds of problems

Double check the ECM ground should be by the coil bracket they can be quite finicky

 

Ecm ground is the one on the bottom of coil bracket? Took a test light to it and it’s fine. All fuses tested out good. Haven’t got to check the codes yet. That’ll be the next thing I do. Has both new crank and cam sensor. Truck did sit for a few months apart but pretty much rebuilt the whole engine besides bottom end internally. Truck ran fine before head gasket went.

 

Happen to know what circuit the cam and crank sensor runs on?

 

The EFI fuse.

When I meant the ECM ground can be Finicky it might test fine but not give a good ground.

A few months possible you have corrosion in the harness plugs unseen by human eyes.

Time to pull any codes it will point you in the correct direction.

Might be time to upgrade to a Multi Meter your test light might show a connection that is under the voltage needed

 

I have a multimeter on hand. What exactly should I test

 

I checked the spot for the efi relay and it’s getting power

 

Please pull your codes.

Your just driving blindfolded

Did your new sensors come from Toyota or After Market ??

 

I’ll get the codes pulled asap! Sensors are aftermarket. But neither the crank or cam connectors from the harness are getting power

 

I have a 96 2.7l wiring diagram, but not 97. According to the 96 diagrams, both sensors connect directly to the ECU. The ECU shows using both the left fender ground as well as the throttle body ground, depending on which circuit is being referenced.

Not sure if that helps you. Definitely need to check for codes, if any had time to register.

 

1996 info

 

1996 info

 

I think 97 is when they went to the double coil packs and steered away from the distributor. Not sure if that would affect the diagram or not. I’ll take a look at it tomorrow and see. Thanks for the diagrams and info! Also about the ground. Not sure if I have a ground in my throttle body. I was trying to hunt down all the grounds to see if I missed one. Couldn’t find anymore tho. I have the one on the finder that goes to the battery. The one on the front of the lower intake manifold. The one from the firewall going to the back corner of the head. And the one going to the coil packs. And I missing one? Throttle body has a ground?

 

It is a direct connection to the PCM indeed and there is no junction, connection fuse or relay in between the wiring. If you have power at neither I have reason to believe you have a dead computer.

Check and see if you have 12 volts and ground to the sensor. If you don't have a 5 volt reference at one of the pins that's a sign that the computer is fried.

 

Do you happen to know which ground the crank and cam sensors use? Thanks for the info. At this point I would gladly replace the computer so I can get rid of the headache of trying to figure this out lol

 

It seems like everything is working. Trucks turning over. Coils have power. Just no power to crank sensor or cam sensor. Which means no spark

 

Hey bud. The ground is redundant without power. Supposedly the ground is by the throttle body though. There should be a multi wire ground somewhere in close proximity to it.

A thought just came to me. If you want to make sure you are not getting power at the PCM and you don't have some sort of short somewhere you may want to go to the computer and check the wiring to make sure the powers are being output there. If they are not, fried computer. The wiring shall be the same color as they are at the sensors themselves. They were single color from what I saw also so they should be easy to identify.

I didn't know you were asking me questions so make sure you hit the quote button so I get the notice that you have a question for me.

 

sorry new to this forum and to wiring really. Thanks for the info. How exactly can I go about checking the wiring at the computer to see if there is power output there? Would like to try that first before I have to cut into my harness and chase a possible short down

 

I’m assuming this is the correct ground tho.