VDC stuck on, re-gen also suffering

[Supernintendo]

Hello all,

I have a new-to-me 2014 Leaf S with 27,000 miles and 11 bars. It's been running fine since I got it a few months back, but for the last week or so two things started happening:
1. VDC light is always on. I try toggling "VDC Disable" on and off, and that separate "VDC OFF" light goes on and off, but the regular VDC light is always lit.
2. Re-gen only lights up one or two circles, even in ECO mode, no matter what brake pressure I use. All 4 re-gen circles have the double-lines around them by the way. This also used to work fine.

I have checked the brake fluid and it's full. Nothing leaking that I can tell.

I do not have LeafSpy. What should I do?

Thanks
Alan

[ElectricEddy]

Hello all,

I have a new-to-me 2014 Leaf S with 27,000 miles and 11 bars. It's been running fine since I got it a few months back, but for the last week or so two things started happening:
1. VDC light is always on. I try toggling "VDC Disable" on and off, and that separate "VDC OFF" light goes on and off, but the regular VDC light is always lit.
2. Re-gen only lights up one or two circles, even in ECO mode, no matter what brake pressure I use. All 4 re-gen circles have the double-lines around them by the way. This also used to work fine.

I have checked the brake fluid and it's full. Nothing leaking that I can tell.

I do not have LeafSpy. What should I do?

Thanks
Alan

Check the 12V battery

[cwerdna]

Out of curiosity, are the tires mismatched? Are they all the same size?

Leaf Spy Pro can be used to read the DTCs (Diagnostic Trouble Codes), if any.

If you have any of the 3 year/36K basic warranty left and the tires aren't mismatched, I'd get it looked at, under warranty ASAP.

My wild guesses are the tires, 12 volt or a failed or somehow disconnected sensor.

[Supernintendo]

Thanks for the tips. The 3/36 warranty is expired. Tires are all the same size and all look nearly new. Front pair is a matched pair and rear pair is a matched pair, but front and rear are different brands. All 4 are same size and have same minimal tread wear.

I'll check the 12V as well.

What I determined this morning was that brake-initiated regen doesn't seem to work at all. The regen bubbles are purely deceleration based. I can let off the gas and get regen, but brake pressure has no effect.

[GerryAZ]

Thanks for the tips. The 3/36 warranty is expired. Tires are all the same size and all look nearly new. Front pair is a matched pair and rear pair is a matched pair, but front and rear are different brands. All 4 are same size and have same minimal tread wear.

I'll check the 12V as well.

What I determined this morning was that brake-initiated regen doesn't seem to work at all. The regen bubbles are purely deceleration based. I can let off the gas and get regen, but brake pressure has no effect.

Your observations are consistent with a wheel sensor (or tire mismatch) problem because the wheel speed sensors do not come into play with regeneration until brake pedal is pressed. Look for broken wires or loose connections associated with each wheel sensor.

[Supernintendo]

Your observations are consistent with a wheel sensor (or tire mismatch) problem because the wheel speed sensors do not come into play with regeneration until brake pedal is pressed. Look for broken wires or loose connections associated with each wheel sensor.

Do you mean the TPMS? Or are there some other wheel sensors involved? Search on the forum just keeps returning TPMS results, and the owners manual doesn't mention wheel sensors at all. Thanks again.

[cwerdna]

^^^
Please read the section under Electronic Stability Control of https://jalopnik.com/this-is-how-abs-es ... -513807036 or http://auto.howstuffworks.com/car-drivi ... ontrol.htm. VDC is an acronym for Nissan's stability control.

https://www.youtube.com/watch?v=MCRLKRluk1w has some visual aids.

[Supernintendo]

Thanks. I get the gist of how ESC works. Only reason I mentioned TPMS was because the only results from a forum search for "wheel sensor" were a million threads on TPMS.

Any advice on how to check these VDC wheel sensors on a '14 Leaf? Owners manual does not mention them and I took a look but didn't see anything that was obviously a wheel speed sensor.

A picture, a location, a visual description of the sensor?

[cwerdna]

^^^
You're best off consulting the service manual (https://www.nissan-techinfo.com/find.aspx?dept_id=10).

To diagnose the problem properly, you will likely need to read the DTCs. I can see some listed relating to wheel sensors on page BRC-57 of the '13 Leaf service manual. Page BRC-45 says

LIGHTING CONDITION
• A malfunction is detected in the VDC function, TCS function, ABS function, EBD function, brake limited slip
differential (BLSD) function, or brake assist function of the ABS actuator and electric unit (control unit).
• For the relationship between warning lamp and DTC, refer to BRC-57, "DTC Index".

[Supernintendo]

^^^
You're best off consulting the service manual (https://www.nissan-techinfo.com/find.aspx?dept_id=10).

To diagnose the problem properly, you will likely need to read the DTCs. I can see some listed relating to wheel sensors on page BRC-57 of the '13 Leaf service manual. Page BRC-45 says

LIGHTING CONDITION
• A malfunction is detected in the VDC function, TCS function, ABS function, EBD function, brake limited slip
differential (BLSD) function, or brake assist function of the ABS actuator and electric unit (control unit).
• For the relationship between warning lamp and DTC, refer to BRC-57, "DTC Index".

Thank you cwerdna I will start digging into that service manual.

I did purchase a Bluetooth 4.0 LE OBD-II and got LeafSpy Pro, and read the DTCs.

1. Assuming the "Ok" lines are not errors, does this really mean that I have 10 trouble codes present on my car??? Ouch. I wonder how many the car lot knew about and just cleared before they sold me the car.
2. Why do some of the lines have a ">" before them and some do not?

Read DTCs 21

>C1116 0009 ABS Stop Lamp Sw BRC-92
C118A 0108 ABS E-Driven Int Brake System BRC-124
U110D 0108 ABS E-Driven Intelligent Brake Comm BRC-130
Ok None ---> AIR BAG
>B2555 0009 BCM Stop Lamp Circuit SEC-69
C1704 0008 BCM Low Pressure FL WT-26
C1705 0008 BCM Low Pressure FR WT-26
C1706 0008 BCM Low Pressure RR WT-26
C1707 0008 BCM Low Pressure RL WT-26
C1A67 0109 BRAKE Stop Lamp Switch BR-98
>C1A70 0109 BRAKE Brake Control System BR-160
Ok None ---> CHARGER
Ok None ---> EPS
Ok None ---> EV/HEV
Ok None ---> HVAC
Ok None ---> HV BATTERY
Ok None ---> IPDM E/R
Ok None ---> METER
Ok None ---> MOTOR CONTROL
Ok None ---> SHIFT
Ok None ---> VSP