Oil level sensor problems!!?!?!?!?!

[B8Nate]

I know this has been touched on before, but I can't quite get an answer here. So let me just start out by saying I got a "low oil level" light on my dash, no big deal it's turbo'd it takes a quart between oil changes I'm used to it, so I add a quart before and the light goes away. This time, it doesn't. So I didn't add anymore than a quart bc I didn't wanna over fill it. But light wouldn't go away, for my peace of mind I drained all the oil and topped it off with new mobil1 oil - 5 quarts. w/ a new oil filter, light still did not go off. So I was told by audi it was "probably a oil level sensor" "they go out all the time" ok cool. so I replace the oil level sensor. Lights still on. I talk to audi again, "ok well it's PROBABLY the hood latch sensor" but my question here before I go buy another sensor and waste my money, do you really think it could be a hood latch sensor? When my hood is closed, it shows closed on the dash, when my hoods open, it shows open on the dash. So to me, my latch sensor isn't bad, I've also searched on forums and people said it could be the "fuse" for the level sensor, but I've pulled every fuse out of the driver door, passenger door fuse box and the trunk and checked them all. The only other thing I can think of is it may be the wiring? I haven't hooked it up to a voltage meter yet but I also don't know what voltage is normal for the sensor. should it be showing 12v? Is there a fuse for the sensor? something I'm missing here


thanks!!

[S4'ed]

So, you replaced the oil level sensor on the bottom of the oil pan? (not the oil pressure sensor that is just below the oil filter)

Could be that the Instrument Cluster has an internal problem : that's what the oil level sensor connects to.

I believe the oil level sensor has 3 wires, +12V power, ground, and the signal (oil level) output. Do you not get +12V on one of the wires?

[B8Nate]

Thanks for the reply @s4'ed , CORRECT, I DID replace the oil level sensor on the bottom of the oil pan, used conductive wire cleaner to clean the ports just in case dirt got in there, between the connections, I have NOT yet got a voltage meter and tested the connection as that is the last thing I have to check, I was just wondering if maybe there was a fuse like in the older b6 and b7 models. I've checked all fuses that I know of in those 3 locations, nothing looks bad. So I guess last thing to check is indeed the wiring? The cluster seems fine, everything else works, mileage, speed reading, cruise control lights up when activated, gas level, shows when doors, hood is open/ closed, etc so seems the display is operating correctly. It hasn't gotten any lower or any higher. MMI just says "add oil - 1 quart max" the display shows "low oil level - add 1 quart max" but never says anything else, so clearly something there is messed up. If the oil was truly low it would get lower on the bar that pops up when I start the car. It's been like that for a month now. I've taken to the stealership like stated above. They don't seem to know what it is and want to charge $100 and keep the car for 3-5 days just to diagnose it.

[B44]

Probably try to disconnect the battery negative terminal for 10 minites and connect it back. Also it can be a bad sensor too.

[B8Nate]

Probably try to disconnect the battery negative terminal for 10 minites and connect it back. Also it can be a bad sensor too.

What's the chances of 2 bad sensors in a row? I'm going to get a voltage meter on it after I get off work today, I guess that's all that is possibly left. Sensor is new, for sure 5 quarts in there, will disconnecting the battery for 10 mins not put it in limp mode?

[S4'ed]

I think I read somewhere that you have to keep the hood open for 5 or 10 minutes, before closing it, to tell the instrument cluster to perform a recheck of the oil level. The exact operating logic of the oil check system seems a bit of a mystery.....

A battery disconnect won't hurt anything...but I don't think it will help. The "disconnect the battery" thing really doesn't do anything on modern cars.....that is a bit old-school, when ECUs did not contain any flash memory.

[WAF]

I think I read somewhere that you have to keep the hood open for 5 or 10 minutes, before closing it, to tell the instrument cluster to perform a recheck of the oil level. The exact operating logic of the oil check system seems a bit of a mystery.....

A battery disconnect won't hurt anything...but I don't think it will help. The "disconnect the battery" thing really doesn't do anything on modern cars.....that is a bit old-school, when ECUs did not contain any flash memory.

Weird never heard about that 5-10 min check.

Do you have a dipstick? I'd pick this up ASAP this way you can always know for sure and it will help troubleshooting this. They are pretty cheap.

[B8Nate]

I think I read somewhere that you have to keep the hood open for 5 or 10 minutes, before closing it, to tell the instrument cluster to perform a recheck of the oil level. The exact operating logic of the oil check system seems a bit of a mystery.....

A battery disconnect won't hurt anything...but I don't think it will help. The "disconnect the battery" thing really doesn't do anything on modern cars.....that is a bit old-school, when ECUs did not contain any flash memory.

Weird never heard about that 5-10 min check.

Do you have a dipstick? I'd pick this up ASAP this way you can always know for sure and it will help troubleshooting this. They are pretty cheap.

yeah guys when performing the oil change, the hood was up for at least 15-20 mins. And I read somewhere in the owners manual that it's only a min or 2 for it to reset. Regardless the hood was up for plenty of time. Definitely 5 quarts in there. I guess I will have and professional audi tech take a look at it after hours someday after Christmas / New Years. I was thinking about getting the dipstick just to have some reassurance. It's the dipstick for the Volkswagen CC isn't it? I've done some research on here and found a part # But don't have it anymore, guess I'll search around for it again!

[WAF]

Too bad you weren't local id give one for free, i've got an ECS one on the way.

[B8Nate]

I think I read somewhere that you have to keep the hood open for 5 or 10 minutes, before closing it, to tell the instrument cluster to perform a recheck of the oil level. The exact operating logic of the oil check system seems a bit of a mystery.....

A battery disconnect won't hurt anything...but I don't think it will help. The "disconnect the battery" thing really doesn't do anything on modern cars.....that is a bit old-school, when ECUs did not contain any flash memory.

Weird never heard about that 5-10 min check.

Do you have a dipstick? I'd pick this up ASAP this way you can always know for sure and it will help troubleshooting this. They are pretty cheap.

Too bad you weren't local id give one for free, i've got an ECS one on the way.

I know but thanks anyways, I'll probably just go to the dealer and get one. Can anyone confirm which of these part #'s is correct? 06H 115 610 B or 06J 115 611 E those are the two that came up for the 2.0 tfsi when searching forums? this is the link I'm going off of, http://a6retrofit.tripod.com/article...ldipstick.html

[Mike@PureMS]

The ECU does indeed monitor the hood latch as part of the oil level sensor check. It needs to see that the hood has been opened and closed, before it will go and re-check the level of the oil. If your hood latch isn't registering correctly, the mmi doesn't know to recheck the oil level and will leave it alone.

You can test it by unplugging the hood latch. There's a connector near the left headlight. You short the connection and trick the computer into seeing the hood open/close cycle.

[B8Nate]

I think I read somewhere that you have to keep the hood open for 5 or 10 minutes, before closing it, to tell the instrument cluster to perform a recheck of the oil level. The exact operating logic of the oil check system seems a bit of a mystery.....

A battery disconnect won't hurt anything...but I don't think it will help. The "disconnect the battery" thing really doesn't do anything on modern cars.....that is a bit old-school, when ECUs did not contain any flash memory.

Weird never heard about that 5-10 min check.

Do you have a dipstick? I'd pick this up ASAP this way you can always know for sure and it will help troubleshooting this. They are pretty cheap.

The ECU does indeed monitor the hood latch as part of the oil level sensor check. It needs to see that the hood has been opened and closed, before it will go and re-check the level of the oil. If your hood latch isn't registering correctly, the mmi doesn't know to recheck the oil level and will leave it alone.

You can test it by unplugging the hood latch. There's a connector near the left headlight. You short the connection and trick the computer into seeing the hood open/close cycle.

just curious though, if the hoood latch sensor was bad, the display on the dash wouldn't show the hood open/close (WHICH MINE DOES in fact show open when opened and closed when closed) so to me the sensor on the hood shouldn't be bad?

[AWDLover]

PM me if you do need another oil level sensor. I bought one to replace what I thought was a bad sensor. Got under the car only to find out a rabbit had chewed through the wires. Repaired the wires and all was good. The dealership has a no return policy on electronics, so now I have a sensor and have since sold the car.

[B8Nate]

PM me if you do need another oil level sensor. I bought one to replace what I thought was a bad sensor. Got under the car only to find out a rabbit had chewed through the wires. Repaired the wires and all was good. The dealership has a no return policy on electronics, so now I have a sensor and have since sold the car.

I will, if I need one. I still need to check voltage. I haven't got to it yet. Anyways, I know about the no return policy bc when I replaced the old one with a new one and the light was still on they wouldn't let me return it.

[S4'ed]

If the dash display can show the hood open warning, your hood switch is OK.

[B8Nate]

If the dash display can show the hood open warning, your hood switch is OK.

thanks that's what I thought, so hood latch sensor GOOD, on my second oil level sensor should be GOOD, no way 2 would be bad in the same day, now all I have left to check is wiring I guess?!?!?!? thanks guys

[S4'ed]

The wire for the +12V power to the sensor is typically fused with a 5 amp fuse...check all of them, and your car has multiple fuse/relay boxes.....under the dash, side of dash, under the hood.

[Crucible35]

You mention you've added 5 qrts of oil. Do you know how much oil the car takes to completely refill?

[B8Nate]

The wire for the +12V power to the sensor is typically fused with a 5 amp fuse...check all of them, and your car has multiple fuse/relay boxes.....under the dash, side of dash, under the hood.

Okay I've been all under that hood and cannot find a damn fuse box, I've found the 2 in each door panel driver and passenger, and in the trunk on the right side. But searched under the hood looking for one. I've installed coils and taken the plastic off by the windshield wipers, all thats under there is an overflow tank for something and the cabin filter thing and the bolts for the struts. I looked next to the engine and it's just the coolant overflow, turbo, engine, oil filter, I don't see ANY fuse boxes under the hood. Only the 3 locations I mentioned.

You mention you've added 5 qrts of oil. Do you know how much oil the car takes to completely refill?

I was told by Audi and my personal Audi/Vw mechanic when I don't go to the stealership to add 5 quarts. Is that not correct?

[S4'ed]

A 2.0T should take about 4.7 quarts for a refill, when you change the filter. 5 quarts is a bit overfilled.

Yes, my bad about the fuse boxes, a B8 A4 does not have an underhood fuse/relay box.

[jfo]

You mention you've added 5 qrts of oil. Do you know how much oil the car takes to completely refill?

It's spec'd in the manual at 4.6L or 4.9 qt.

[B8Nate]

A 2.0T should take about 4.7 quarts for a refill, when you change the filter. 5 quarts is a bit overfilled.

Yes, my bad about the fuse boxes, a B8 A4 does not have an underhood fuse/relay box.

well she's got 5 quarts so she'd def not low. and okay cool I was like surely I'm not that blind, I've done the carbon build up cleaning, flushed and refilled coolant, oil change, installed exhaust, coils surely I didn't miss a fuse box under there.

It's spec'd in the manual at 4.6L or 4.9 qt.

that's what I thought, so it's def got enough, and 2 sensors can't be wrong, so back to wiring I need to check I guess.

Does anyone know what voltage I should be looking for? Will the sensor itself have a 12v reading since it's a thermal voltage reading will it have a voltage resistance coming off the snesor when at operating temps? or just the connection coming from the car?

[B8Nate]

for anyone reading this in the future, the correct part # is indeed 06J 115 611 E for the dipstick accurately in the 2.0 tfsi motor, I've confirmed with both Audi, VW and a private mechanic who specializes on Audi/VW

[B8Nate]

STILL NEED HELP!!!!

OKAY, so still having an issue. Finally got under the car and checked the sensor/plug harness area. Cleaned it all up. Unplugged and re-plugged everything up. LIGHT WILL NOT GO OFF.

So I hooked my multi-meter up to it. Put the positive in the positive terminal and negative to ground terminal on the harness coming from the car. Only got 2 volts, this is with the car ON but NOT running. I turned the car off and obviously didn't get any voltage. But with the car ON and not running, I plugged the positive to positive and took the negative and grounded it to the FRAME OF THE CAR. And got 11.9-12.3 volts?

So to sum it up, on multi-meter if I put red (+) to the positive wire terminal on the harness and black (-) to the ground wire on harness I get 2 volts. When putting red (+) to the positive wire terminal on the harness and putting the black (-) negative to the frame of the car it reads 11.9-12.1 volts.

So does this mean I need to splice into the ground wire on the harness coming from the car and ground it to my frame?? Or what??

[piotrowr]

If the dash display can show the hood open warning, your hood switch is OK.

Not true, I had 2 hood latches replaced for this exact issue by dealer under warranty. It could be stuck in a closed always position. If it does not sense it was opened/closed, will not run reset routine to check oil level.

[B8Nate]

Not true, I had 2 hood latches replaced for this exact issue by dealer under warranty. It could be stuck in a closed always position. If it does not sense it was opened/closed, will not run reset routine to check oil level.

my hood latch switch shows open when open and closed when closed. SO I think it's okay.

[B8Nate]

GUYS is there anyway to just code it out via Vag-Com? I just want to remove that one setting. I don't care to see if my oil level is low or get a warning, I change my 0w40 oil and filter between 3,500-5,000 miles. I check it frequently. I bought a dipstick from Audi that will be here next week. I've never had a car with an oil warning. And never had an issue. I can manually check it myself. I just want the annoying nagging light off my dash and the beep every time I start the car. I know it's a thermal switch so I can't really use resistors or wire it to think the sensor is there and working, but is there something else I can do????? Please help!!!

[B8Nate]

Another update. With no help from anyone on here yet I tried yet another failed thing towards this annoying issue, I spliced into ground wire on the harness. Grounded it straight to the frame. Finally got 12volt reading coming from the harness. Plugged it back into sensor. Opened hood to reset the oil level. Even disconnected battery for 10 mins. Plugged back up. Started car till operating temps. Turned off. Started back up. STILL HAVE THIS MOTHERF**KING LIGHT ON!!!! Wtf else can I do. I'm seriously getting sick of this and refuse to go to the dealership.

[Audi 4 Life]

Since nobody else is making any suggestions I will... awhile back I had a situation similar to this on my 3.0 what ended up being the final fix was to run an entire new harness to the ECU. If you do it right and clean with a new sensor that should either fix the issue or at least tell you the issue lies with something other than the sensor and the wiring. Hope this helps.

[S4'ed]

The lack of ground at the sensor harness seems like a problem, but strange that your added ground wire did not fix your problem. I assume you have a 2.0T? Perhaps this helps, this info below, is from the S4 3.0T V6 wiring diagram (I don't have the 2.0T wiring diagram)

Oil Level Sensor pin 1, black wire with blue stripe, gets +12V (only when car is running) thru 5 Amp fuse #2 in the fuse panel B. Fuse panel B is inside the plastic weatherproof box that is at the base of the windshield, the same box that the engine ECU is located in. Access thru the cowl area, remove black plastic cover by the windshield wiper arms.

Oil Level Sensor pin #2, Brown wire, this gets connected to ground somewhere in the engine harness, at a multiple sensor grounding point.

Oil Level Sensor pin #3, red wire with white strip, goes to Engine Control Module (ECU). I thought this went to the Instrument Cluster, but I was wrong.

[S4'ed]

TSB

55 "Low Oil Level" message is on in the DIS or MMI

55 13 32

2023967/6

July 30, 2013

Supersedes Technical Service Bulletin Group 55 number 13-30 dated May 28, 2013 for reasons listed below.

Vehicle Information

Condition

"Low Oil Level" message is on in the DIS or MMI.

Technical Background

The hood must be open for at least 30 seconds for a reset of this message to be performed. The message is not reset in the DIS/MMI because the hood has not been recognized as being opened due to an inoperative hood contact switch.

Production Solution

Improved hood contact switches have been put into current production vehicles, and a software change with improved logic is planned for production.

Service

Check hood contact switch: Use the VAS diagnostic tester to read MVB 26 in the J393 - Comfort System Control Module (address word 46) after the hood is opened and closed:

A) If the value does not change, replace the hood contact switch, following the applicable work instructions listed in the ElsaWeb Repair Manual.

[B8Nate]

The lack of ground at the sensor harness seems like a problem, but strange that your added ground wire did not fix your problem. I assume you have a 2.0T? Perhaps this helps, this info below, is from the S4 3.0T V6 wiring diagram (I don't have the 2.0T wiring diagram)

Oil Level Sensor pin 1, black wire with blue stripe, gets +12V (only when car is running) thru 5 Amp fuse #2 in the fuse panel B. Fuse panel B is inside the plastic weatherproof box that is at the base of the windshield, the same box that the engine ECU is located in. Access thru the cowl area, remove black plastic cover by the windshield wiper arms.

Oil Level Sensor pin #2, Brown wire, this gets connected to ground somewhere in the engine harness, at a multiple sensor grounding point.

Oil Level Sensor pin #3, red wire with white strip, goes to Engine Control Module (ECU). I thought this went to the Instrument Cluster, but I was wrong.

OMG! I owe you so much!!! The fuse box location was wrong. For the 2.0T we don't have a fuse panel under the trim by the windshield wipers or the ECU. We do however have the fuse panel next to the ECU in the trunk. I checked the fuse. And guess what. It wasn't there. I guess when I checked fuses before I replaced sensor. I somehow left it out, dropped it, not sure but it wasn't there so it the dash display never reset when I changed the sensor. I used a spare fuse to put in that slot. Turned car on. Light did NOT appear. I owe you a ton man!!! It's been nagging me for almost 2 months. Thank you so much!!

[AOW162435]

Excellent!



Andreas

[van462]

I see you have it fixed but I'll add some info in case someone else has issues down the road. One way to verify the red/white wire that feeds the signal to the signal to the ECU is to measure from the harness pin to gnd (car power off). It will read approx 10k ohms. Combined with the voltage reading from S4 above all the wires can be checked. The oil level sensor wiring harness joins with the turbo sensors and becomes the main engine wire harness that down the exhaust cam and around the back of the block.

I poked around while I was doing my timing chain last night.

[B8Nate]

I see you have it fixed but I'll add some info in case someone else has issues down the road. One way to verify the red/white wire that feeds the signal to the signal to the ECU is to measure from the harness pin to gnd (car power off). It will read approx 10k ohms. Combined with the voltage reading from S4 above all the wires can be checked. The oil level sensor wiring harness joins with the turbo sensors and becomes the main engine wire harness that down the exhaust cam and around the back of the block.

I poked around while I was doing my timing chain last night.

absolutely, I didn't check that w/ ohms, just volts, but that sounds spot on - correct!!

Also I noticed when I had the harness unplugged testing wires and turned car to the on position, it started right up but the display read 'Faulty Oil Level Sensor" NOT "low oil level" like mine had previously been saying,
so if you have a bad oil level sensor that has little or no power coming from it, and/or in this case the plug isn't plugged up or worse case, a wiring issue, it would say "faulty oil sensor" not "low oil level" like mine showed, I didn't have a Vag-Com cable or I would of known this a month ago

But regardless, for some reason just that fuse missing didn't cause an electrical issue with it for it to display "faulty sensor", it just never let the display update after I changed oil and sensor and caused the light to stay on no matter what I did... Weird I know basically just froze on there bc it never had a chance to update itself, so basically anyone reading this in the future, very first make sure your fuse is good, then check the sensor, then wiring last, bc as far as costs goes it also goes in that order and I am glad I only spent the $3 I spent on 5 fuses (and only uses 1) still got 4 left :) ... than buying a new wiring harness which I was on the verge of.

[Aks1982]

I'm having the same issue. Which fuse did you leave out/put back in?

[thatauditech34]

I know this might be a huge shot in the dark, BUT last time I had this issue on a customer car I actually found coolant ingress to the ECM and it was creating low resistance (short) on the signal wire to the oil level sensor. As one person said, if your cluster is showing the hood is open/close then the hood switch is fine. When you get a meter check pins 1&3 on the level sensor plug for 12v. Pin 2 to ground should be 4.9-5v.

Edit: I wasn’t going to read the entire thread but I see you fixed the issue.

Sent from my iPhone using Tapatalk

[Hermaphrodite]

I'm having the same issue. Which fuse did you leave out/put back in?

yeah, me too....what fuse is it??!!??

[Smac770]

oil level thermal sensor G266 is on fuse 2 in fuse panel B, the fuse block that is in the ECM box under the plenum cover, 5 amp.

[Hermaphrodite]

Thanks, I will take a look. I didn't realize there was a fuse block under the hood. My '09 A4 B8 has one on each side of the dash and a third one in the trunk....I thought 3 was a lot!!