Okay here’s the specifics...
When I bought car the instrument panel on dash never showed what gear I was in, (no light ever came on) so I was unaware that one was even supposed to come on until recently. But car ran fine, never noticed any issues with shifting accept that if I didn’t put it into 4th gear and left it in D it would pop out of gear or into a lower gear every time I jumped on the accelerator. But putting it over into 4 position eliminated that so that’s how I always drove it.

Now several months later I’m with the current issue. I left sunroof open and it rained. Next morning I hopped in and drove about 3/4 of a mile to the gas station to put air in tire. It drove like normal, put it in park to air up tire and went to take off and stuck in low gear. Tried shifting other gears, nothing changed. Tried turning off and on, still stuck.

Researched online and was certain it had to be the shifter due to getting wet, so I ordered another one and installed. Still no change.

I’ve checked for codes and no codes other than my usual o2 sensor codes are coming up.

I got underneath and pulled out the plug that also tends to be culprit due to fluid getting into seal and although there’s fluid around it, seals seemed to be still good because inside plug looked dry and clean.

Also want to note that intermittently prior to this happening, the car wouldn’t always Go into P park when shifted to P position, so my key would’nt come out and car wouldn’t restart until I messed around with the shifter a few times then I’d get it to lock so key could be removed. Now however, the car is shifted into Park position, but it will shift freely to all other gears without me pressing the brake pedal first. I’ve also recently replaced the brake pedal switch and brake booster so I’m pretty sure that’s not bad.

please help. Not trying to keep dumping money to trouble shoot this issue. But with no codes coming up it makes it hard to figure out why I can’t get it out of limp mode.

thank you for any and all help!

 

Welcome Angie,
I dont recall w163 in 1999 had any PRND display in the cluster. My daughter has a 99 ML430 - no PRND display in the cluster.
What scanner are you using? Some scanners (less expensive ones) are not able to read modules, like the TCM and others.

 

i wasn’t sure about the lights in instrument cluster but that’s really the least of my concerns anyways, unless it were to have any relevance to my current situation thus why I did mention it... as for scanners I used a Bosch one from o’reileys that claimed it read TCM and PCM error codes. My check engine light has never came on either, but I’ll still have codes when I connect odbd reader so I’m guessing light is just out or something

 

It doesnt mean that this scanner can read ALL TCM PCM codes of ALL vehicles. You have to read thru their literature, and verify with them that it will read those on a w163, not just at what they "generally" claim or advertise.
You have codes because they never have been erased. They're stored in memory. And take note, just because a scanner can read the error codes, does not mean they can erase the codes. Your scanner has to specifically say it is capable of reading, erasing, (or re-writing, in a few cases) in their literature. You have to get thru all the BS advertising they do, or search on these forums or ASK one of the many members for a recommendation.

 

yes i do know that this particular code reader does not erase codes for sure... but there have ever been any transmission related codes show up at all. Only o2 sensor codes or misfire codes when I had a bad coil. But those codes seemed to clear once i disconnect battery and replaced coil. Anyways, I honestly don’t know if what’s wrong with my car would make a code come up, that’s where I’m unsure. If it’s something to do with the linkage on the shifter that won’t have a code will it?? I just can’t call this tbh. It’s weird that I can shift the car from park into any gear without having to press brake pedal for one... then being stuck in limp mode I am at a loss on this one

 

You wont necessarily get a code with linkage issues.
With '..shifting the car from park into any gear without having to press brake pedal....', replace your brake switch. It's a cheap fix.

EDIT: Just reread your brake switch replacement already. Humm, what are the chances your replacement switch failed? It has happened before - testament from other members.

EDIT2: Ok, you mentioned rain thru the open sunroof ---------------> water into the cabin -----------> shifter got wet (good possibility) ---->
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