New here, but would appreciate some help. I have a 96 Bronco with the 5.8 and it keeps coming up with error code 443. Also the overdrive light on the shift lever blinks off and on. I don't know if they are related or not. I know the code means VPWR circuit open, but I have checked the VMV solenoid and believe it to be working. Thanks

 

You're talking OBDII "0443" not OBDI "443" right?

P0443 Evaporative Emission System Purge Control Valve Circuit

 

Yes it is OBD 2 and it is 0443 code

 

Not sure my diagram be right for yours, shows red wire key "on" 12v+ power to it, the ground provided by computer via a gry-yel wire when command given do so.

Canister purge is open during "warm cruise" so testing it be a little tough without rigging some kinda lest light in the cab or meter seen while driving.

Wouldn't directly effect trans (well might), first test for power key "on" at red wire.

Lots of things get power from that same circuit, including for example the trans solenoid pack.

 

I ran jumper wires to the VMV and it opened the solenoid letting vacuum thru. I also warmed the truck up and put a test light to the ground side to check when ground occured when I revved the motor to about1500 RPMS the light came on. The red wire going to the valve does have power going to it.

 

Good test, chance it might not have worked that way as PCM didn't detect vehicle at cruise speed at the time. Same time never see anything stating it had to be other then opens "warm cruise", worse you'd had do was take it for ride a minute!

Anyway your testing of it shows its in working order so clear the code, drive it see if it reappears.

Any adverse symptoms from the trans other then the flashing O/D light? I mean you notice no shifting issues of any kind? speedo works normally?

 

No the transmission shifts fine, the overdrive turn off works. Turn off overdrive and the tach jumps up. The overdrive light comes and goes.

 

Anybody got any ideas been banging head against the wall. Still no answers.

 

TCIL light blinks and VMV error codes....they both get power from the same place: from the load side of the EEC relay. S136 (Splice) is common to both and a few other circuits. My book is cryptic states S136 is located "Engine control sensor harness, near T/O to brake warning resistor/diode assembly" Not sure where that is.

The VMV is fed through connector C129 located "RH rear of engine compartment, on heater blower plenum"

The transmission solenoid pack is fed from S136 to connector C109 located "LH side of engine compartment, top of wheel well" then onto splice S169 located "Back lamp switch harness, in T/O to transmission".

I would start looking for a supply voltage problem....