rafterman191

I have been out in the cold trying to trace this issue down. Was getting code p0449 and changed the evap fuel tank pressure sensor. Didn't clear codes so I carefully pulled the underhood fuse box and checked pin/wiring and found nothing out of the ordinary. Put back together and no crank with code u0101. Found no issues with grounds wiring etc. This car was running fine just prior to starting in on this. Tying to clear codes, I can hear a clicking from the throttle body each attempt to clear codes. I press clear and hear click and the throttle body valve moves, but codes remain as well as no crank. Any ideas?

Oldblue

donbrew

Why did you replace the fuel tank pressure sensor instead of the EVAP vent valve? Where are you getting your info? P0449 is the EVAP vent valve CIRCUIT that is on fuse #64 underhood fuse box.

My idea is that when you put the fuse box back together one or more of the pins got bent or pushed out of the connector. U0101 means there is a B+ short to ground on the ECM.

firemangeorge

quote "This car was running fine just prior to starting in on this"

Well. Seems obvious that you messed something up when putting it back together. Not sure what answer you're looking for on this forum.
Time to redo your "work".

rafterman191

I took the underhood fuse box apart, inspected the wire harness plug ends and pins on the back of the fuse/relay housing. Blew them out with some light compressed air and reassembled. I replaced what is shown is this video...

rafterman191

I am using a cheap Menard's ODB II/CAN scan tool to try to clear codes as well as read. I have also tried disconnecting battery for hours and overnight.

I have redone my work a couple times. First time, it restored my driver side headlight and removed an airbag message. Reinstalling the fuse box also removed what had been a steady anti-theft light issue after the first attempt.

ETA: Looking over codes I had taken pictures of after the first fuse box disassembly, I see a p2176, u0101 & p0443. After the second reassembly, codes remaining are u0101 & p0449.

donbrew

What does the tank pressure sensor have to do with anything in that vid?
Did you do the testing that he did? He should have added checking fuse #64.
Obviously there is a electrical connection problem in the fuse box and/or the ECM.

rafterman191

Sorry, it was the canister vent valve sensor that I replaced due to the code p0449 per the video. After replacement I could not get code to clear and had read the tsb about the potential for a harness wire terminal coming loose in the underhood fuse box. I had previously experienced issues with this fuse box needing tightened down and fuses reseated to make the common gremlins go away, but had never had it all the way apart. Anyway, I've had it apart more times than I wanted now. I agree that it's likely I fried the ECM somehow. What do you think the significance of the moving/clicking throttle body/valve when I try to clear error codes is (if any)? It literally clicks and moves the valve each time I try to clear the stored codes (using the scan tool).

donbrew

The clicking is caused by the short that U0101 is complaining about.

Solenoid is NOT the same as sensor.

rafterman191

So if the clicking coming from the throttle body (tps?) is the result of a short, where is the short potentially occurring? Thanks donbrew for responding.