Hello folks --

This morning we had some heavy rain, and I took my 03 DII (71k miles, bought late January) to go and play in the puddles with my little boy. Much fun was had!

However I am now faced with a few issues.

1) Bank 1/Sensor 1 O2 reading low voltage

Two codes have registered, and I've checked the voltage trace coming off the sensor. Sure enough it's not oscillating up and down like it used to, just shows a much milder cycle between 0V and 0.2V or so. I did disconnect and reconnect the connector just in case there was a bit of water trapped inside, but honestly it looked dry and clean, so I suspect water's gotten into the sensor housing.

Question: should I order the replacement sensor now or give it a day or two to see if it sorts itself out?

2) Odd transmission behavior

I pulled over to talk to a neighbor just before coming up my driveway on our return trip, and put the truck in Park. It then was unwilling to shift into either Reverse or Drive, took a few cycles back and forth on the shifter, then worked and I trundled up the driveway.

Later, when poking at the oxygen sensor issue, I started it up to pull it into the garage. I noticed that, from a cold start, the shift position indicator showed 'P', correctly showed 'R', didn't show anything for 'D', then correctly showed '3', '2', and '1', on the way down.

Then I reversed, starting from '1'. '2' and '3' showed correctly, once again nothing for 'D', then initially nothing for 'R' for a few seconds before it appeared and the transmission thunked into gear. It shifted back into 'P' fine, but then the green M and S lights started flashing. At that point it's obviously in limp-home because pulling away in D starts in a higher gear, which I assume is 3rd.

Checked for codes, nothing transmission-related. Checked battery voltage. 12.6V with the truck off, 14.3V at idle. Looked at the XYZ switch, didn't see anything obviously wrong, but haven't pulled it apart to look more closely.

Turning the truck off and then on again resets the flashing green lights, but the sequence I described above about what appears in the shift position indicator appears to be repeatable. Still no codes available via my generic OBD2 scanner.

Question: what to check next?

I'm reasonably handy for basic things but this is my first LR so I don't have a good gut feel for troubleshooting sequence. I have RAVE but couldn't find anything matching my particular symptoms, and don't know if there might be separate codes accessible only via Testbook or similar.

Thanks all in advance.

twj

 

If you got water in your transmission you should start looking for a replacement.

 

I wouldn't doubt that but these were puddles and splashing, not fording or deep-water crossings, so it seems water getting in through the vent tube would be challenging, or at least such small quantities that they don't worry me too much?

The drive back on dry roads was ~35-40 miles and everything felt fine, shifted normally, etc. It was only the handling of the shifter which seemed to reveal an issue.

thanks
twj

 

These are sealed transmissions and frankly pretty hardy units. I would drain the transmission and see if it looks milky or perhaps even burnt/worn out and replace the fluid following the steps provided here on the forum. It's actually pretty easy since Land Rover was nice enough to give us a drain plug on the transmission. You could even drop the transmission pan and replace the filter. Its a little more difficult but nothing any shade tree mechanic can't handle. I would do both. You will need a pump to get the fluid back in the fill hole, as it is on the side of the transmission. $10 at Walmart for the pump. I think I had to put 5 quarts back in mine after draining. It holds a lot more, but that is all you're able to get out at a time unless you take it somewhere that can do a flush. As for the sensor, I would wait a few days and see what it does on its own. If no change then I'd replace it.

Always check every fuse! It wouldn't hurt to check for any kind of sticks, leaves, mud or garbage stuck up in any of the externals.

 

I'd think that the XYZ switch on the side of the tranny may be full of water / muck, and the electronic switching of tranny computer is disturbed. It can be removed, opened, cleaned up, resealed.

 

Thanks -- I think that may be correct. Further troubleshooting revealed a P0705 code, but I was in the midst of resetting the computer since the voltage traces on the O2 sensor appeared to be improving (not enough, as it turned out...)

Anyway after going to pick up pizza without any transmission issues, got back in to come home and the car started directly into limp-home mode. Pulled over, ignition off, back on, shifted into D (with the several second pause before the indicator illuminated) and made it home without further incident. Shifting fine up and down the gears, no weird noises or other symptoms.

So yes, I'll pull the XYZ switch, clean it with contact cleaner, and refit it. Presumably there are many threads on the subject (I will check after posting) but I'll welcome any tips, special tool requirements, etc just in case.

thanks
twj

 

Give the O2's some time to dry out before ordering new ones. They'll be fine. It happens to me sometimes. When going to my in-laws they have a road where you literally have to cross two flowing streams (those suckers are deep in some spots). Needless to say, I never turn down an opportunity to go visit them

 

Agreed.

 

My o2 sensors do the same after mud riding and subsequent high pressure undercarriage spraying. I've taped around my front sensors to try to keep water out, but it still finds a way sometimes. I usually misfire intermittently on idle and low speeds for about a week after. It eventually fades away.

 

Grap a can of compressed air from an electronics store and some dielectric grease... open up the plugs, spray them out with the air, use a soft toothpick to scrap off any hard contamination on the contacts, dab some dielectric on it, plug it back up and good to go.

yea i doubt you damaged the tranny itself, but water getting up (splashing) on top might get into the plugs on top... pop em open, blow and clean them out and reconnect and go. mind you there will be alot of dry dust, road crap and dirt up there anyway, and spash of water instantly makes it mud which can find its way into the plugs with the water...after the water dries out you still might have the crud in/around the plugs causing the issues.