p1296 solved!!!

[Audiophil]

Hello Bug fans! After almost 5 years of trouble free (except for those headlight bulbs that last only a year :P ) driving, my bug's check engine light came on.

Of course being a member on the ORG for years I took it to Autozone and received a free code read. The code was p1296 - which thanks to Fowvay from the ORG means something is wrong with the coolant system.

Researching the old forums and doing basic trouble shooting (such as - is the coolant system functioning - clogs, overheating, etc.??..) I determined it was the temp coolant sensor. $9 bucks plus $2 for the seal and my check engine light is off. BIG BIG thanks to the ORG!!


For those looking for a how to, it takes all of 15 minutes... don't let any stealership charge you ~$200 for the repair!

1. Buy temp sensor and O ring. (if you are REALLY cheap I have seen these on E-Bay motors for like $4 - my stealership wants about $9).

2. Recommended while at the dub parts counter get some g12 coolant - just in case you loose alot - you shouldn't, but it would suck having to drive with low coolant in your bug to go get some. (done properly you will lose VERY little - if you are like me - see below - get the g12)


3. On the 2.0 engine the sensor is located on the coolant line coming from the top of the radiator and runs along the right (driver's side) of the engine. On the driver's side of the engine this hose connects to a "junction box" which has the sensor on top and facing the interior of the bug (4 wires).

4. If your engine has been cool for atleast an hour, remove the clip below the sensor by pulling it towards you.

5. Remove the sensor by pulling it away from the hose.
(note: I am a dumbass and let the engine sit for only ~15 minutes...coolant shot out of the hose in a big blast when I removed the sensor - VERY VERY luckly none got in my mouth or eyes - just all over my hands - don't be a dumbass - wait ATLEAST an hour or so)

6. Seat new O-ring on new sensor and make sure it is all the way to the top of the metal part of the sensor.

7. Insert NEW sensor in hose and press firmly downward so it sits in the hole snugly. Replace plastic clip below sensor on coolant hose.

8. Unplug 4 pin connector from old sensor and plug into new sensor - if the pins line up you should hear a tiny click as it locks into place - DON'T force it.



Start Bug - check for leaks around sensor and any other hoses you may have moved during installation.

Now at this point others have said the CEL then turned off on their Bug, or after a few minutes or so. Mine did NOT turn off... so not having a code reader, here is what I did...

Look at the coolant resevior in the upper left hand corner of the engine compartment. There is a two pin sensor connection near the top - unplug this. (grasp plug with thumb and index finger and push, then pull plug out from coolant housing. )

Start your Bug - after a few seconds (me about 20-25) your red temp light should flash and your instrument cluster will beep at you. Turn off engine and reconnect coolant resevior sensor connection. Restart your bug and the CEL should be cleared.

(note: if this was a resevior problem - I would guess that the sensor in/on the resevior would trigger the coolant light, not the CEL - others have seem to have confirmed this. If you get a p1296 you might want to try unpluging this sensor before replacing the coolant hose one. My guess is once the resevior error is cleared by reconnecting it - this clears the CEL. You could of course just find someone with a VAG-COM and do it the right way! )


Now this worked for me, I certainly hope it helps someone else out here on the ORG. I am an electronics technician by profession and I like to tinker with things, but I am NO WAY a mechanic, if you break your Bug you can't sue me or Jeff Croft. :P


Thanks again to members like Fowvay who posted the codes and others that frequent the ORG!!! You all are awesome.


-Mark

[maxajon]

Your instructions are great. I was able to locate everything. I just have a couple of questions:

1. You refer to "8. Unplug 4 pin connector from old sensor and plug into new sensor - if the pins line up you should hear a tiny click as it locks into place - DON'T force it." Where is this 4 pin connector and is this done after the new sensor is inserted back into the hose?

2. Would you happen to have the part number for the temp sensor?

[rcy]

If you let your car sit overnight so it's stone cold, you won't lose a drop of coolant. I didn't anyway.

The 4pin connector is the electrical lead that plugs into the sensor. Unplug the wire leading to the old sensor, remove old sensor, insert new sensor, plug the wire you unplugged into the new sensor. It should take all of 5 minutes...I can't believe the stealership gets away with charging more than maybe $20 including the parts.

[maxajon]

How long did it take for the CEL to go off? I replaced the old temp sensor with a new green one and the CEL did not go off. I also tried unplugging the sensor on the reservoir until the instrument cluster temp light flashed red and I got a beeping warning. After plugging it back in, the CEL is still on. BTW, when the CEL first came on, I took it to Autozone and the VAG-COM read P1296 1 of 1. Should I take it back to Autozone for another reading?

[hannaco]

Yes. See if they will clear the code for you. Just tell them that you want to see if it will come right back on.

[maxajon]

So... I get into my NewB this morning to go to Autozone and see if they'll clear the code for me. I start her up and see that the CEL is still on <sigh>. BUT! As I'm waiting for her to warm up...TA-DAAAA! The CEL goes off!!! I guess it just took a few starts.

THANKS: Audiophil, rcy and hannaco! You all just saved me loads of cash!

[Audiophil]

Glad I could help out some fellow ORGers... here are some pics to go with the How-To:

Temp Sensor location...



Getting closer...



Finally, by the side of the engine is this...



Four wires coming out of the green "thing" is the coolant temp sensor. Hope this helps!

-Audiophil

[heatherm]

Where can I find a temp sensor and O ring for my car? I have looked on ebay...maybe I am looking in the wrong places? Any help would be great!

[hannaco]

If you have a VW dealer nearby, start there. ECS tuning, Impax Foreign Auto Parts, or 1stVWparts.com
The cost has gone up since last year.

[Smileybug]

How did you manage to get your sensor for 9 bucks at the dealer?! Mine charged me $25 for mine!! And I lot a ton of coolant when I did it...but the car was pretty warm still as I had to run back to the dealer to get the right sensor. And it was a Saturday in winter so light was limited.
Good write up though!


*word of warning* there are two different sensors for the cars. One is D shaped and one is square. There was a switch in '99 between them. The dealer gave me the wrong plug the first time, even though I gave them my VIN so make sure its right!

[heatherm]

Ok guys I need your help....I drive a 98 auto 2.0 and need the new sensor, saw them on this site but not sure which one I should get. Should I get the blue one or the green one??? Or does it not even matter? Thanks guys still new at all this!

http://www.ecstuning.com/stage/edpd/...el=&engine=2.0

[Smileybug]

The green one is the right one. They redid them because the blue ones were failing. Green one is the way to go!

[volcombug]

I just did mine yesterday and it only took like 15 or less. I did lose coolant but I was able to get some that my Dad had . I am just hoping that there are no leaks. I think I might need to put more coolant in though but all looks good for now.

[heatherm]

So I ordered the green one off of ecs tuning and got it and it will not fit my bug its like the plastic is the "D shaped" plug and too deep for the 4 prongs to connect to it, so will the blue one fit my car? That is what is in there now and its square.

[IHeartNB]

Mine was blue with squared connector. Its a 1999 NB. For those who are wondering, the d-shaped and squared one have different part #. Check your original one first to see which one fits yours. Like stated in the previous post. Its basically a 5-minute job. One thing to add is that, hold down the sensor when you remove the plastic clip. I didn't do that, the sensor popped up and I lost about half a cup of coolant . That was when the engine was stone cold as well.

D-shaped: 059 919 501A
squared: 059 919 501

[Dalemg55]

Thank You I followed your instructions to a tee and changed sensor and had code cleared and alls well in turbo"s" camp. thanks

[antonym]

This also works for cooling hose flange plug!

[adisman]

This DIY was great!! I followed the directions and in no time had the sensor changed in my 2002 VW Beetle. I had to erase the DTC using my code reader though to get the check engine light off. I'm running the drive cycle now to confirm the problem was fixed. If not, I'll change the t-stat.

However, I do have a few questions that I was hoping someone might be able to answer.

1. Right next to the temperature sender (more towards the front of the car, but on the same section of pipe) there is a little plug with what looks like a phillips head cutout. Do you know what that is?

2. Does the temperature sender send the temperature to both the dash gauge and to the OBD2 or are there two sensors?

3. When I removed the temperature sender, coolant didn't come out like I thought it would. Does that mean I am low? I looked in the reservoir, and it looked plenty full.

Thanks,
Aaron

[noR]

1) No.
2) Dash is connected to ECU, same sensor runs both dash & obd2.
3) Normal.

[adisman]

Thanks for the quick response.

As far as the plug is concerned, I thought I'd try and give a little better explanation. It has the same size opening in the coolant line as the opening for the temperature sender and also uses the same type of clip.