octakaidecagon
VIP Member
Firstly, I wanted to say that this forum has been a brilliant source of Cali information during my ownership thus far, thank-you so much to all who have contributed!
I have a 2015 T5.1 California SE 140hp, which I recently took for its replacement of cambelt, water pump, and aux belt. (First change was at 4 years old, this was its change at 8 years old).
Shortly after this work I have been getting a 'Check oil level' amber indication on the MFD (no other lights/indications) which lasts for a few seconds after switching on the ignition then it disappears. Checking the oil level via dipstick shows it to be normal. The van drives normally, and Oil Temperature is within the normal range. Opening the bonnet (e.g. to dip the oil) clears the indication until I do a reasonable length of drive (approx 50-100 miles) at which point on the next start-up the indication appears for a few seconds then disappears, and then after 10-30 mins of driving it appears for a few seconds then disappears.
An example of the indication (ignition on, van not yet started):
During the above events I spoke with the garage and the van is booked in for investigation in a few days, but in the meantime I have been doing a bit of research so I am well informed. Based on the symptoms, I suspect most likely this is a sensor or wiring issue.
I crawled under the van to see if there were any obvious wiring issues. I noticed that in the underbody, on the left (passenger side) just aft of the front wheel, there is a set of connectors, and one of these connectors is free to move slightly, rather than being clipped into a nearby plastic retainer.
See the following pictures:
I used erWin to look up this connector, and found it via the "Fitting location diagrams" as "3-pin connector −T3bc− , black, on underbody, near apron". I then looked up connector T3bc in the "Current Flow Diagrams" and it shows that on one side of this connector, the 3 pins are connected to G266 which turns out to be the "Oil Level and oil temperature sender" (itself located at the bottom of the oil sump). And on the other side of this connector we have a ground, a power connection to a fuse, and a connection to J285 (which is the "Control unit in dash panel insert").
So, a possible cause of the fault is a loose connection / abraded wiring at this location, due to the connector not being fastened.
However, G266 is a combined Oil Level and Oil Temperature sensor, and VW docs show that level and temperature measurements are sent via PWM on the single signal wire to the dash. Therefore, it seems likely that a broken/intermittent connection would affect both the Oil Level and Oil Temperature reading, yet since this issue first occurred I have driven with Oil Temperature displayed constantly on the MFD and it is responding normally to driving conditions.
Another thing I noticed whilst looking underneath the van in this area is that the silver heat shield looks to be bent, and I can't quite determine if this is normal or not. See the pictures above. The wiring to the connector T3bc is cable-tied to the heat shield and so I am wondering if perhaps the heat shield has been bent pulling the connector T3bc away from its retainer.
I have scoured the internet for a picture or video clip of the underside of a T5.1 Cali/van depicting this same area so I can see what 'normal' looks like for this heat shield, but can't find such an image. Would any kind forum member be willing to crawl under their T5/T5.1 van, just aft of the front left wheel and take a picture of this same area so I can compare? I would be most appreciative!
I will update any progress on this thread in case someone has a similar issue in the future.
I have a 2015 T5.1 California SE 140hp, which I recently took for its replacement of cambelt, water pump, and aux belt. (First change was at 4 years old, this was its change at 8 years old).
Shortly after this work I have been getting a 'Check oil level' amber indication on the MFD (no other lights/indications) which lasts for a few seconds after switching on the ignition then it disappears. Checking the oil level via dipstick shows it to be normal. The van drives normally, and Oil Temperature is within the normal range. Opening the bonnet (e.g. to dip the oil) clears the indication until I do a reasonable length of drive (approx 50-100 miles) at which point on the next start-up the indication appears for a few seconds then disappears, and then after 10-30 mins of driving it appears for a few seconds then disappears.
An example of the indication (ignition on, van not yet started):
During the above events I spoke with the garage and the van is booked in for investigation in a few days, but in the meantime I have been doing a bit of research so I am well informed. Based on the symptoms, I suspect most likely this is a sensor or wiring issue.
I crawled under the van to see if there were any obvious wiring issues. I noticed that in the underbody, on the left (passenger side) just aft of the front wheel, there is a set of connectors, and one of these connectors is free to move slightly, rather than being clipped into a nearby plastic retainer.
See the following pictures:
I used erWin to look up this connector, and found it via the "Fitting location diagrams" as "3-pin connector −T3bc− , black, on underbody, near apron". I then looked up connector T3bc in the "Current Flow Diagrams" and it shows that on one side of this connector, the 3 pins are connected to G266 which turns out to be the "Oil Level and oil temperature sender" (itself located at the bottom of the oil sump). And on the other side of this connector we have a ground, a power connection to a fuse, and a connection to J285 (which is the "Control unit in dash panel insert").
So, a possible cause of the fault is a loose connection / abraded wiring at this location, due to the connector not being fastened.
However, G266 is a combined Oil Level and Oil Temperature sensor, and VW docs show that level and temperature measurements are sent via PWM on the single signal wire to the dash. Therefore, it seems likely that a broken/intermittent connection would affect both the Oil Level and Oil Temperature reading, yet since this issue first occurred I have driven with Oil Temperature displayed constantly on the MFD and it is responding normally to driving conditions.
Another thing I noticed whilst looking underneath the van in this area is that the silver heat shield looks to be bent, and I can't quite determine if this is normal or not. See the pictures above. The wiring to the connector T3bc is cable-tied to the heat shield and so I am wondering if perhaps the heat shield has been bent pulling the connector T3bc away from its retainer.
I have scoured the internet for a picture or video clip of the underside of a T5.1 Cali/van depicting this same area so I can see what 'normal' looks like for this heat shield, but can't find such an image. Would any kind forum member be willing to crawl under their T5/T5.1 van, just aft of the front left wheel and take a picture of this same area so I can compare? I would be most appreciative!
I will update any progress on this thread in case someone has a similar issue in the future.
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