What could i have done wrong
I googled p0888 Chrysler pacifica and found this link
P0888 Chrysler Description
"The transmission control relay is used to supply power to the solenoid pack when the transmission is in normal operating mode. When the relay is off, no power is supplied to the solenoid pack and the transmission is in Limp-in mode. The relay output is fed back to the Powertrain Control Module (PCM). It is referred to as the Transmission Control Relay Output circuit or switched battery.
After a controller reset (ignition key turned to the run position or after cranking engine), the controller energizes the relay. Prior to this the PCM verifies that the contacts are open by checking for no voltage at the switched battery terminals. After the relay is energized, the PCM monitors the terminals to verify that the voltage is greater than 3 volts."
It appears for some reason that relay on your car isnāt turning on and powering up the transmissionās solenoid pack. No electrical power to the solenoid pack, no shifting. B/c the solenoids in the transmissionās valve body are what activate the shifting process in modern electronically controlled automatic transmissions.
Itās hard to imagine how work done on the hub would affect that. Iām thinking maybe itās just a coincidence. i.e. it was going to happen anyway, and it just decided to happen the same time as you did the hub work. If you had to loosen electrical connectors for the hub work, that could have something to do with it I suppose. I presume the only electrical connector was for the wheel speed sensor, right? You could try disconnecting that and see if the shifting problem goes away. Of course another problem will show up, lack of the wheel speed sensor. But that shouldnāt prevent shifting. It might turn on the CEL and the stability system warning light though.
Thereās some chance I guess that your hub worked created an electrical glitch. So another idea is to disconnect the battery for an hour or two then re-connect. That may reset the software and get it working again. If that doesnāt work, you may need to go to a dealership and have them reset the transmission software using their scan tool.
But what Iām thinking ā provided no harness wiring was damaged or pinched during the hub job ā is you need to have a transmission shop figure out whatās wrong with that relay. You could try just replacing the relay, cross your fingers. Do you know where that relay is located? If not, maybe somebody here knows.
Check your ground connections.
1 Like
Yes only thing disconnected electrically was speed sensor. Already tried to disconnect battery overnight. No go. So Iāll try to unhook and see what happens. If not Iāll take to shopš. Thanks for everyoneās help.
I canāt believe it. Had a friend of a friend look at it. It was just a little 20 amp fuse that was missing. How could it run just fine before without the fuse?!??
Probably the fuse got blown in the same time frame as the repair. How? Youāll probably never know. It may well have been a coincidence. Itās also possible thereās a remaining transmission problem and the fuse will blow again. Hopefully not, but if it does at least youāll know what the problem is. Thanks for letting us know the final resolution to the problem. Best of luck.
One my good friend who used to own a number of old domestic cars in such a case was suggesting to go and trace any wire harness[es] which might rub against the metal.
He used to have a lot of Chrysler products in particular.
In his experience, mysteriously blown fuses often trace to some āshiny spotā on some wire, shorting to the ground where harness rubs against something.
I had similar experience once with old Nissan Sentra, where fuse for radio and other accessories was blowing up: found a kink of cable touching the metal rib, sure enough with a tiny wear spot where copper was visible - Iāve replace a number of fuses before tracing this one.
1 Like
But there was no fuse in that spot!
wire shorting can be anywhere else, not necessarily next to original repair site
moreover, wire could get shorted only in certain conditions, like you have to get car lifted by one side for example before unibody bending would make wire to short
unfortunately, it is very hard to troubleshoot, as your repair site might have been right/front for example and short can be in the central area, were transmission is located or even somewhere in the backā¦ hard to tell as I have no experience with Pacifica
we can only tell one fact: fuse was blown, finding the reason for it to blow might take a lot of careful wire tracing/examination and it is generally very time consuming
if that fuse blows again, at least you might have an idea on what to do next.
do not try installing āa bigger fuseā there, this may be a legitimate issue
i watched a video on repairing the P0888 issue. there were chafed wires inside the main wire harness. they backprobed the relay in the main box and found it had a trickle amount of power but no current flow when car was running so the relays would not energise and make trans work.
You should identify the missing fuse for the crowd here, it may help to understand how it could have worked before or if was even part of the actual problemā¦
EATX FUSEā¦#36 IN fuse box
hmmm ā¦ so it was shifting fine w/no fuse in that spot, then you took it in for a hub repair, then it wouldnāt shift after the hub repair, then you put a fuse in that spot, and it started shifting ok? Thatās indeed a mystery. About the only thing I can think of is that there actually was a fuse in that spot before the hub repair, and for some reason the fuse was removed as part of the hub repair, and they forgot to replace it.