So I just got done changing neutral safety switch and starter relay and now nothing works. I try to start but it doesn't crank at all. Van had 3/4 tank before I did the swaps and now it shows empty. Another thing that caught my attention is the obd2 port isn't working now. I have verified all fuses and relays, all are good. I'm currently in the process of trying to reset the passkey3 system. If anyone has any input on my issue please help.

 

Neutral safety switch and now not cranking, I would guess switch is in wrong or you just got a bad one. But combined with a now faulty fuel gauge and powerless OBDII port?

Can you start at the beginning? Like before you changed the switch and relay? How much time has passed? What are the chances that someone stole your gas? Why are you trying to reset the passkey system? IIRC don't you have to have a working key to do that?

 

The van is not actually mine. The owner said it had an intermittent issue of not wanting to start originally(not crank over). I had changed the trans oil and filter and it started after that(had to verify oil level). I replaced the NSS and I have already verified that it is placed correctly and that it does work. I tried to start it with the current issue of no crank, empty fuel(even though tank has at least 3/4), and no connection at obd port also the PRND,etc isn't lighting up. I did disconnect the battery each time I made the swap for the NSS and the relay. Also the fuse for pcm/crank shows no power as well. I changed the starter relay at this point to have no change. I have checked every fuse and all have power except the pcm/crank fuse. I'm going to check relays this evening when I get out of work.

What I'm wondering is if the pass key set itself off could this be what's causing my issues or is it something else?

 

I haven't had the security issue on my Venture, but I know on my '00 Impala everything still worked and it just wouldn't crank.

When you said the OBDII port wasn't working...no power or just not communicating? I would think even with a passkey issue that simply putting the key in position #2 it should be communicating. And IIRC power is always there. The passkey only does one thing, prevent the vehicle from starting - everything else should still work.

I'm wondering if you just have an ignition switch problem. Electronics (modules like the PCM) are more likely to fail but switches (and relays) do get buildup on the contacts which will cause intermittent problems, like you said this has.

 

The obd port does have power, just not communicating. The fuse for crank/pcm has no power. Everything seems to work that I can tell except the gas gauge showing empty and not being able to crank over and no communication with obd. I'm trying to avoid sending it to the stealership. Tomorrow I will dig into the steering column and see if I can figure out what's going on in there.

 

Update:
Ignition switch apparently fried itself and a ground wire running the span of the dash. Replaced the ignition switch and combed through the wire harness running through the dash and replaced the ground wire that fried. Still no change in conditions. Also noticed I can shift the gear selector without pressing the brake.

So in all I have no power at the pcm fuse, no communication with the obd port, fuel reading empty when tank is at 3/4, warning light flashes from low batt to low fuel to security and repeats, no crank and the ability to shift without depressing the brake pedal.

I'm completely confused right now.

 

the power to the ecm sense fuse in the under hood fuse block comes right from the battery. it feeds a entire battery feed bus which powers the alternator sense fuse, air pump, cooling fan 1....do these fuses have power?


check the cig fuse as it powers the data link connector....ie scan tool plug.

 

I don't believe any of the fuses are blown and I believe everything is getting power except the pcm fuse. I will double check in the morning and update.

 

Ok I have checked every fuse and relay. Nothing is blown, all relays are good and the pcm/crank fuse still has no power. My obd scanner does power up it just doesn't communicate.

 

Scanner probably isn't communicating because because the computer isn't getting power, which is also probably why the gas gauge shows empty and the drive letters aren't lighting.

I'll try to remember to check the manuals for a wiring diagram tomorrow and let you know if I find anything.