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Hi All,

I have a vw golf 4 1999 model which has a tranny behaving funny.It has gears 1,2 and 3 but 4th not engaging.Replaced G68 AND G38 and got the codes erased by a generic scanner.Still the problem persists.What could be wrong.Gear 3 engages at about70km/hr.
It would prob be helpful to know what codes you were getting before, as well as what codes you are getting now, if any. Otherwise, sounds like maybe a fluid level issue or failure of clutch and/or hard parts, but that's just my guess based on my experience dealing with other auto transmissions. I'm just now learning about the VW's, involuntarily of course! ;)
 

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trans problem too..

Hello all. I've been reading a couple of these posts and I have a question or two if anyone would like to chime in. I have a 96 gti auto with 189640 on the clock. My son has been driving the car so i dont know if the problem was gradual or what. When I crank the car in park, if you give it gas the car wants to move forward, but bogs down. Reverse-nothing, ND3 car moves forward as if you were driving, 2nd and 1st nothing like being in park. You can also crank the car in neutral but as soon as it starts it goes forward ( cranked the car from outside the car and had to chase it a couple of feet!) You have to turn the car off and put it in neutral in order to push the car. Also upon starting the engine has a party horn type sound that changes with with the engine speed. I scanned the computer with a generic scanner and came up with code P0715. So my questions are should i just replace the G38 or G68 sensor and retest or buy a used tranny from the salvage yard for $100 + $28 for the 30 day warranty and the sensors too? Thanks for any and all suggestions!:thumbup:
 

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Mine was the P0715 code, referring to the G38 sensor, so that's where I started, and so far it has corrected the issue!
Thanks again!
I guess I should have read post 12 better eh?? dOH!
 

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It would prob be helpful to know what codes you were getting before, as well as what codes you are getting now,
I'll 2nd that emotion.
 

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99 Jetta Auto Tranny not shifting G68 Replaced Heartbroken

Hey guys, new to the forum here. Please help if you will.

99.5 or Newer body style Auto trans 2.0

First it quit shifting from second unless I revved over like 5k and held it. Soon as that happened I quit driving it. Light came on. I pulled the code reader said no signal from output speed sensor.

Well then I unplugged the both sensors G68 and G38 plugged back up then it shifted for like a day. I saw the dash go into limp mode as well. With shift lights. Quit shifting. I guessed that the output sensor just went bad and then completely went out.

Then it went right back to not shifting. So I replaced the easy sensor the G38 NO fix then replaced the one under the tranny mount which I believe is the output speed sensor and NO fix. I don't know where the ground wires are to check. Everything I can see looks good but no idea whats going on. Been like two weeks getting wrong parts and finally getting the right one through the Stealership for like triple the money and cant return it. That is the sensor under the tranny mount.

Tried doing the tranny resets maybe didn't do it right on the reset I dont know. :(

Please help if you have any ideas.

Thanks,

Fred
 

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Fluid Level

Have you checked to make sure the transmission has the proper amount of fluid inside it. Volkswagen calls it a lifetime fill but I have experienced first hand the need to add fluid. I had to fashion a little device of my own to fill the transmission fluid to the correct level.
 

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Well after 2 weeks of not driving the car and it driving me crazy thats what it was. It has a small leak at one of the seals. It was low on fluid. WOW. They did some things right but really screwed up if you ask me. Put a frekin dip stick check on there instead of under the car nonsense.

Thanks for the reply.

If you have tranny issues pop up. First thing :screwy: check the fluid. Normally I would have. But got to go all out over engineering.
 

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2002 Jetta 4 speed auto(not Tiptronic) 2.0L gas 110,000 miles
Code(s) in photo below taken from VCDS(VagCom). G68 sensor the best place to start? I know that might seem obvious but reading many replies in here is a bit confusing as to the G38, fluid level, ground wires, etc. Or go for ground check first, then G68? I'm assuming(hoping) the other fault codes are due to the G68?
Physical symptoms. Won't shift out of first until 4,000 rpm and will shift to 3rd only once unless you stop and either shut car off or shift into park and get going again. Will not ever shift into 4th. And it early downshifts just below 2,000 rpm.
 

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2002 Jetta 4 speed auto(not Tiptronic) 2.0L gas 110,000 miles
Code(s) in photo below taken from VCDS(VagCom). G68 sensor the best place to start? I know that might seem obvious but reading many replies in here is a bit confusing as to the G38, fluid level, ground wires, etc. Or go for ground check first, then G68? I'm assuming(hoping) the other fault codes are due to the G68?
Physical symptoms. Won't shift out of first until 4,000 rpm and will shift to 3rd only once unless you stop and either shut car off or shift into park and get going again. Will not ever shift into 4th. And it early downshifts just below 2,000 rpm.
Since the computer uses the G68 in its calculations to determinte the 00653 and 01192 codes you have to ignore those till the g68 code is gone. You can do some testing or maybe just try replacing it.
 

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Little device

Have you checked to make sure the transmission has the proper amount of fluid inside it. Volkswagen calls it a lifetime fill but I have experienced first hand the need to add fluid. I had to fashion a little device of my own to fill the transmission fluid to the correct level.
Will you be able to share your little device? To make one.
Thanks
 

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Have you checked to make sure the transmission has the proper amount of fluid inside it. Volkswagen calls it a lifetime fill but I have experienced first hand the need to add fluid. I had to fashion a little device of my own to fill the transmission fluid to the correct level.
Will you be able to share your little device? To make one.
Thanks
If you dont want to take the time to make one you can fill the trans through the g38 speed sensor hole. Just have to pull the breather. See the following link.

http://kansascitytdi.com/01m-filter-change/

We made a pump that is powered from our "jump box" that pumps fluid in for us, but on a 01m its easier just to pull the breather and the g38 sensor and use a funnel.
 

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Hello,

I'm having a transmission sensor problem on my 2002 Jetta (2.0L, 01M). I had accidentally spilled coolant above the transmission and it began intermittently throwing P0722 (output speed sensor no signal) and P0730 (incorrect gear ratio) and going into limp mode, so I assumed I got coolant on the female end of the G68 sensor (the end not located under the transmission mount bracket). I crudely cleaned the connection with a toothbrush and the car took itself out of limp mode. However, I decided to replace the G68 just in case. Interestingly, I found out that the G68 was frayed and corroded in the middle of the cable, so I thought the replacement would have fixed the problem. Unfortunately, it immediately went back into limp mode and now throws only P0730.

Could the connection between the female end of the G68 sensor and the cable that connects it to the TCM be bad due to corrosion from the coolant? How might I check that with a voltmeter? Or does anyone know what the cable that connects the G68 to the TCM is actually called and if I could easily replace it?
 

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Suggestions

Find somebody who has a VCDS (or invest in one yourself) and see if the computer is registering a signal from your G68 sensor. Also consider draining and refilling the transmission fluid.
 

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Thanks for the quick response, nsmiller!

My local mechanic said the computer is seeing a G68 signal, but that it's inconsistent. He, like you, hypothesized that changing the transmission fluid and filter might solve the problem. Is it true that you should reuse ATF for my vehicle model and not fill it with new fluid? The guy I spoke with was convinced that new ATF would cause the tranny to start slipping.
 

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No, I've never heard of reusing tranny fluid. I would fill it with fresh fluid, but make sure that the fluid meets VW's specifications. Do not just go use an off the shelf ATF fluid unless you are sure it meets VW's spec. Be sure to change the filter as well.

I have 3 VWs and have changed the tranny fluid with new on all of them. 1 is a 99 cabrio with an 020 tranny (5 spd manual). Another 98 Jetta with a 01M tranny. And a 09 TDI with the DSG transmission which actually calls for a fluid change ever 40K miles.

A quick google search and I found this:

http://faculty.ccp.edu/faculty/dreed/Campingart/jettatech/01m.pdf
 

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One more thought

I once had a G68 speed sensor code on my 01M transmission. It went into limp mode. I suspected a bad sensor, so I disconnected the battery and pulled the senor out. I examined it for physical damage, there didn't appear to be any, so since I didn't have a sensor to put back in immediately I put the original back in the car and the code went away. It has never come back since. That was over 50K miles ago. I just attributed it to maybe the car got struck by lightning or someone was trying to mess with my car while I was parked somewhere. Either way, disconnecting and reconnecting the sensor worked in that case.

If a fluid/filter change doesn't resolve your problem, consider checking the wiring for continuity with a standard ohm meter.
 

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I've never checked a wire's resistance before (n00b). Are the ohms that each wire should read listed anywhere? Or is that now how it works? I have a Bentley but can't seem to find any actual values.
 

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If a wire is good the resistance should be pretty low. The actual value is irrelevant. If you touch the two terminals of a ohm meter together it will read out some very low value. 0.5 Ohms, perhaps. This is the internal resistance of the multimeter. A straight copper wire will generally have pretty close to the same resistance. More importantly, if there is a break you should have infinite resistance aka current cannot flow. The display screen will be the same as if you hold the two terminals apart while not touching anything. If you need further explanation there are lots of youtube videos out there demonstrating continuity testing with a multimeter.
 

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Okay guys, here's my G68 sensor story. It may help someone who finds themselves in a similar situation.

As with most of the posts in this thread, my '99 Beetle would intermittently go into limp mode. Got the same P0720/P0715 codes y'all are seeing, so I figured it couldn't hurt to replace both sensors, Of course the first one was a breeze, but yeah, that G68 is a pain in the ass. Jack up the transmission, take out the mount, etc., etc., you know the drill.

Anyway, finally got all the work done and the car put back together only to find that now instead of being in limp mode intermittently, it was now a permanent feature. And code P0720 will no longer clear using a generic OBD-II scan tool. Well crap.

So yeah, I spend hours looking up wiring diagrams and information about the sensor. While I don't know the actual pin numbering on the G68 connector, I did find the 800-900 ohm resistance on two of the pins, so it seems the sensor itself is okay. Yep, time to open up the dash. That took more time than it should have, as I discovered it was filled with leaves inside so I had to spend a while vacuuming them all out, sheesh.

Finally got to the TCM and got it unplugged. Measured the resistance between the two wires to the sensor and I get an open circuit. Well crap, looks like a wiring issue; must have been exacerbated when I replaced the sensor. I had a hard time trying to physically follow the wires from the TCM to the sensor, so I finally ended up plugging a wire into the sensor end and measuring the end-to-end resistance. As it turns out, both wires are fine, I'm getting a good connection all the way.

What the hell is going on??? Well, I didn't know the pin numbering when I measured the resistance on the sensor, but having to trace the wires, now I do. So I double-check the sensor resistance and guess what? Instead of the resistance being measured across pins 1 and 2 as in the wiring diagram, I'm getting the measurement between pins 2 and 3! What the heck?

Sent a message to the eBay describing the issue, but got no response.

So here's where I'm at; I've got a sensor installed that seems to be functional, but is wired wrong. Mine has the older style square connector and as I'm looking at it, I realize it's symmetrical and the only thing that would keep me from being able to plug it in reversed are the two little ridges on the plug. So what the heck, I went ahead and filed them down and plugged it in backwards.

Guess what? The sensor works perfectly now! Fault code is gone, no longer in limp mode, and no codes coming up on the scan tool. Car shifted a little rough to start with, but after driving it for a few days it's fine now; I figure unplugging the TCM made it have to relearn the transmission.

So the long and the short of it is, I bought a very cheap (like under $14) that is wired backwards. Rather than going out to buy the next more expensive (and presumably correct) sensor, which involves pulling the transmission mount, I filed off the ridges on the side of the sensor plug, allowing me to plug it in reversed from what it should be, and now it works, transmission all fixed.

SMDH
 
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