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Drove through *big* puddle, OBD code P087B

30K views 12 replies 7 participants last post by  Miller88 
#1 · (Edited)
so, my wife drove through a giant puddle

Almost immediately after, the check engine light came on with code P087B, and wouldn't drive faster than 15 MPH (so says my wife).

Had it towed home, and let it dry out.
Unplugged battery and plugged it in again after like 30 minutes (hoping for computer reboot?)

Now, the symptoms I see besides the code is:
1) it won't go in reverse
2) when in park, won't rev past 4k (don't know if it always did this? but thought I'd mention it)
3) when door opens, that sound it makes to prepare the transmission takes 3 times longer than it used to and sounds "funny", like more clicks and clacks than usual.
4) maybe more, when it wouldn't go in reverse I got scared and turned i off.

Engine runs and sounds about like it did before, doesn't sound like any misfires.

I looked up P087B, and couldn't find what the "B" stands for. The code seems to be related to Transmission Fluid Pressure Sensor / Switch C Circuit.

Any idea what the "B" means, and if this is something I can fix on my own, or about what the cost might be?
 
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#2 ·
#2 is normal, rev limiter to prevent damage.

P0870B is apparently a Ford proprietary code (not generic) & I didn't find anything on it with a quick search - NOT the P0870 generic code for fluid pressure sensor IMHO, no fluid pressure to monitor in these.

You've got the TCM on the trans that's both a computer for that and the gear shifting actuator (we're actually not sure how much of the "computing" is done there) and two clutch actuator/sensors. Water in the large connectors for any of those could cause a problem by itself, and I suppose it's a possibility.

Hopefully someone has access to the right code list to narrow it down more for you.

Welcome to FF
 
#6 · (Edited)
I don't work for Ford, but I'll check to see if I have the code tomorrow as well.

There's a module by the driver's side tire/radiator (PCM? BCM?) that doesn't look too well-sealed from the elements. Might be related to that. Maybe it'll solve itself.

EDIT: And, of course, our system is acting wonky this morning and not letting me log in.
 
#7 ·
According to the service manual, DTC P087B is "Clutch Position Sensor B Circuit Range/Performance".

Sounds as if there may be/may have been moisture in the connector for the B clutch position sensor.
 
#8 ·
According to the service manual, DTC P087B is "Clutch Position Sensor B Circuit Range/Performance".

Sounds as if there may be/may have been moisture in the connector for the B clutch position sensor.
Thank you (and everyone else)
This may sound like a dumb question but can someone give me an idea of where this is and what it looks like so I can do a visual inspection?
 
#10 ·
So, I gave up. Didn't have the experience or the tools to troubleshoot anymore. I appreciate the help I received.

Wanted to share the disposition of my experience. Ford replaced the Transmission Control Module (TCM), which with labor and parts came out to about $1200. Afterwards, said the clutch wouldn't engage, and at this point insurance paying for it, so they just went ahead and fixed it. I don't know what the problem was for the second fix, but it only added $150 to the total bill. Haven't seen the invoice yet.

I don't know if this could've been done cheaper, or if it is a DIY type of problem. Thought I'd share in case someone else experiences something similar.
 
#12 ·
paying out of pocket vs warranty

Normally I'd agree, and argue it. However, it broke immediately after driving through water that was way too high to drive through. Unless the defect was somehow making it more susceptible to water damage? But it doesn't look like it.
 
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