No Start, No Click, No Check Engine Light

[GTV]

I'm attempting to wrap up a big cylinder head off job on my 2007 LC. The only other relevant task I did was to replace the starter "while I was in there." It's back together now and as a first test I wanted to do a compression check.

Battery is two months old and tests at 89% according to my gauge. The negative lead was disconnected for the last 5 weeks while the work was being done.

Turning the key, everything seems normal, but it's as if the starter is not receiving power at all. Upon closer inspection the check engine light, which should illuminate while starting, is not turning on. I believe this means the ECU is not receiving power(?)

I checked the main fuse, the fuses in the engine compartment and the EFI/ECU related fuses in the kick panel. All look good.
I tried plugging in two different OBD readers, neither one will connect. I assume the OBD is powered through the ECU.

I'm exhausted and at a loss at what to look at next. I sincerely appreciate any advice.

 

[white_lx]

Turning the key, everything seems normal, but it's as if the starter is not receiving power at all. Upon closer inspection the check engine light, which should illuminate while starting, is not turning on. I believe this means the ECU is not receiving power(?)

Besides the obvious check fuses, powers and grounds, etc: I assume you had the CAM sensor removed in this job? If the CAM wires were damaged it could shorten out the reference voltage. In that case the ECM will be unresponsive with no CE light.

 

[GTV]

Besides the obvious check fuses, powers and grounds, etc: I assume you had the CAM sensor removed in this job? If the CAM wires were damaged it could shorten out the reference voltage. In that case the ECM will be unresponsive with no CE light.

Grounds are solid. We tested the ECU/EFI relay last night and it passed.

Assuming CAM is camshaft and not an acronym for something else? As I remember that is the sensor that is located near the intake between #3 and #5. It was removed for the work and reinstalled.

I should I mention that it did start and run prior to all of this work.

I tried two different OBD readers. One was a Bluetooth style, would not connect at all. The other is a more “professional” type unit and it also failed to connect but did read a battery voltage of 12+ while it was trying to connect.

I’m going to go through the motions in the FSM to see if the ECM is receiving power, etc. Hopefully I learn something from that but honestly I’m not all that hopeful.

 

[TLCOVERLAND]

Check your Block Assembly Fusible that is located by the battery.

​

 

[white_lx]

Assuming CAM is camshaft and not an acronym for something else? As I remember that is the sensor that is located near the intake between #3 and #5. It was removed for the work and reinstalled.

I was referring to the camshaft position sensor (CMP) at the front of the engine, behind the timing belt cover. The wires are easily nicked by the sharp edges of the water pump. If it happens to ground the reference voltage, it will take down the whole ECM. If you can reach it, you can unplug it at the front of the cover and see if the ECM will show the check engine light again.

You can also check some other sensor voltages, to see if that part of the power is at least up and alive. The easiest one to reach is the MAF sensor.

 

[89BIGBLUE]

Double check battery voltage.
These guys are sensitive to voltage.
They'll light up stuff, but if there's not enough juice, they won't crank.
Headlight left on "auto" for a few weeks parked led me to this.

 

[GTV]

Found the issue, it’s a runner!

Went through the troubleshooting procedure in the FSM. @white_lx was on the right track. I checked voltage and resistance at the ECU, kept pulling sensor connectors, wasn’t getting anywhere. The last sensor that needed to be checked and pulled was the SAIS pressure sensor, under the intake manifold. Removed the intake (again) and there was the smoking gun, I accidentally switched the 1 and 3 wires on the connector when I replaced it. We removed the connector, turned the key on and the CEL illuminated. Swapped the two wires, tested the CEL again and reinstalled everything, performed a compression check and it fired right up.

The culprit (after I corrected the wiring):

Original connector showing correct wiring:

I sincerely appreciate everyone’s help!

 

[Trapper50cal]

I'm so glad you found the solution!

 

[2001LC]

Good job and interesting. I wouldn't have though, the S.A.I wires would have caused the issues you saw. Good to known!