seat leon mk3 1.6tdi - Seat leon electrical gremlins - anyone any thought - flat4fanatic

Hi, hoping someone might be able to point me in the right direction of a problem that's starting to drive me nuts:

Hi, hoping someone might be able to point me in the right direction.
On the wife's MK3 Leon (2016 1.6tdi with stop/start) had a load of odd electrical issues recently. link deleted [moderator]
Firstly 12v socket and blower motor stopped working.

Was working fine, stopped next journey, worked again then died permanently
Took the blower motor out, works fine with 12v direct to the fan.
Fuse had blown on the 12v socket so replaced that - may have been related or may have been one of the kids plugging in their dvd player.
Thought it might be the controller/resistor pack, swapped for an apparently known good 2/h one still nowt.
No codes on vcds

Checked all fuses in both fuse boxes - behind glovebox and in engine bay.
Few days later on a long 4 hour trip I dropped the e/window and the traction control/abs/headlight range warning lights all came on. plus odd ball stuff like winter tyres and cornering light errors (which it doesn't have).
My cousins garage up north read loads of low voltage warnings and rear left abs error. He swapped the abs sensor, checked wiring back to abs pump and all ok so he thought it might be the pump.

Still suspecting electrics as more random warnings on on the way back I put a new battery on it and all warning lights went away.
Blower still not working though
Fast-forward a couple of weeks and the mrs driving it yesterday, put the rear wiper on, which didn't activate straight away, but when it did all the warning lights came back on again.

I found this thread on another forum which said blower motor, 12v socket and rear wiper shared a circuit which makes me wonder if it's a faulty relay. However, the thread was for the mk2 model and theres no 373 relay on this car.
On the advice of a mate who's good with this stuff, left ignition on, plugged a phone charger into 12v socket and removed each relay in those 2 locations 1 by 1, hoping this would i/d the one for the blower/rear wiper/12v socket circuit. However, power to the socket stayed on the whole time so assuming there's no relay.
Ran vcds again -
No obvious damp issues (stopped working in the middle of the recent 6 week dry spell). At a bit of a loss now apart from start checking every bit of wiring on the car for damage.

Car drives spot on.

Latest vcds scan below with the non-fault bits removed

Any ideas would be greatly appreciated, Thanks

Friday,30,April,2021,15:29:31:41541
VCDS -- Windows Based VAG/VAS Emulator Running on Windows 10 x64
VCDS Version: 21.3.0.0 (x64)
Data version: 20210226 DS325.0
link deleted [moderator]




VIN: VSSZZZ5FZGR009866 License Plate: SEATV3
Mileage: 108266km-67273mi Repair Order:


Chassis Type: 5F-SE37 (5Q0)
Scan: 01 03 08 09 15 16 17 19 42 44 52 55 5F


VIN: VSSZZZ5FZGR009866 Mileage: 108266km-67273miles


01-Engine -- Status: Malfunction 0010
03-ABS Brakes -- Status: Malfunction 0010
08-Auto HVAC -- Status: Malfunction 0010
09-Cent. Elect. -- Status: OK 0000
15-Airbags -- Status: OK 0000
16-Steering wheel -- Status: OK 0000
17-Instruments -- Status: OK 0000
19-CAN Gateway -- Status: Malfunction 0010
42-Door Elect, Driver -- Status: OK 0000
44-Steering Assist -- Status: Malfunction 0010
52-Door Elect, Pass. -- Status: OK 0000
55-Headlight Range -- Status: Malfunction 0010
5F-Information Electr. -- Status: OK 0000

-------------------------------------------------------------------------------
Address 01: Engine (2D2D2-CXXB) Labels:. 04L-907-309-V1.clb
Part No SW: 04L 906 056 CL HW: 04L 907 445 B
Component: R4 1.6l TDI H06 2370
Revision: 22004001
Coding: 01114012432519090000
Shop #: WSC 00049 770 00124
ASAM Dataset: EV_ECM16TDI03004L906056CL 002005
ROD: EV_ECM16TDI03004L906056_002_VW37.rod
VCID: 79F93CB0F87B174384-802C


1 Fault Found:
25126 - Databus
U1123 00 [039] - Received Error Message
Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 6
Fault Frequency: 1
Mileage: 108266 km
Date: 2021.04.29
Time: 15:09:38


Engine RPM: 0.00 /min
Normed load value: 0.0 %
Vehicle speed: 0 km/h
Coolant temperature: 52 °C
Intake air temperature: 29 °C
Ambient air pressure: 990 mbar
Voltage terminal 30: 12.453 V
Unlearning counter according OBD: 40
CAN status - engine control module: 0
Cruise Control System (CCS): status: Initialization


Readiness: N/A


-------------------------------------------------------------------------------
Address 03: ABS Brakes (J104) Labels: 5Q0-907-379-ESP-V1.clb
Part No SW: 3Q0 907 379 T HW: 3Q0 907 379 C
Component: ESC H32 0393
Revision: 00000000 Serial number: 61335000000399
Coding: 20EE8A9224200975007F060641C9240451249000608224F200 410070C002
Shop #: WSC 00049 770 00124
ASAM Dataset: EV_Brake1UDSContiMK100ESP 034033
ROD: EV_Brake1UDSContiMK100ESP_034_VW37.rod
VCID: 4B95B678E26755D366-801E


2 Faults Found:
4197 - Rear Left Wheel Speed Sensor
C101C 14 [137] - Open or Short to Ground
MIL ON - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 1
Fault Frequency: 1
Reset counter: 8
Date: 2021.04.29
Time: 15:09:39


16417 - Display for Tire Pressure Monitoring
C1146 02 [137] - Signal Failure
MIL ON - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Reset counter: 8
Mileage: 108266 km
Date: 2021.04.29
Time: 15:09:48



-------------------------------------------------------------------------------
Address 08: Auto HVAC (J301) Labels:| 5G0-907-426.clb
Part No SW: 5F0 907 426 M HW: 5F0 907 426 M
Component: AC Manuell H02 1001
Revision: 00001K09
Coding: 00100104200100001000000000001000
Shop #: WSC 00049 770 00107
ASAM Dataset: EV_ACManueBHBVW37X 003017
ROD: EV_ACManueBHBVW37X_003.rod
VCID: 3467CD849F992A2B17-8060


1 Fault Found:
459779 - Local Databus
U1030 00 [009] - Electrical Malfunction
[New feature! Extended UDS fault detail is only supported by current gen. interfaces]
Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 6
Fault Frequency: 2
Reset counter: 8
Mileage: 108266 km
Date: 2021.04.29
Time: 15:11:33


-------------------------------------------------------------------------------
Address 19: CAN Gateway (J533) Labels:| 5Q0-907-530-V1.clb
Part No SW: 5Q0 907 530 AF HW: 5Q0 907 530 M
Component: GW MQB High 212 2223
Revision: -------- Serial number: 21051510800445
Coding: 030100F40F087300EA000040000F0001000105000000000000 0000000000
Shop #: WSC 00049 770 00107
ASAM Dataset: EV_GatewConti 013020
ROD: EV_GatewConti_013.rod
VCID: 75E13080D4637323E0-8020


Generator:


Multifunction steering wheel control module:
Subsystem 2 - Part No SW: 5F0 959 537 B HW: 5F0 959 537 B
Component: E221__MFL-PR6 H04 0130
Serial number: 000000000A1238290415
Coding: 002000


Battery Monitoring Control Module:


1 Fault Found:
66567 - Local Databus
U1030 00 [009] - Electrical Malfunction
[New feature! Extended UDS fault detail is only supported by current gen. interfaces]
Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 5
Reset counter: 8
Mileage: 108266 km
Date: 2021.04.29
Time: 15:09:38


Terminal 30 power supply: 12.2 V
Terminal 15: On


-------------------------------------------------------------------------------
Address 44: Steering Assist (J500) Labels:| 5Q0-909-144.clb
Part No SW: 5Q0 909 144 R HW: 5Q0 909 144 R
Component: EPS_MQB_ZFLS 125 1061
Coding: 0103
Shop #: WSC 00049 770 00124
ASAM Dataset: EV_SteerAssisMQB 012140
ROD: EV_SteerAssisMQB_012_VW37.rod
VCID: 43859E58CA379D939E-8016


2 Faults Found:
20228 - Databus
U1123 00 [008] - Received Error Message
[New feature! Extended UDS fault detail is only supported by current gen. interfaces]
Intermittent - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 6
Reset counter: 48
Mileage: 108266 km
Date: 2021.04.29
Time: 15:15:31


Motor status: 01
System status: Driving mode
Supply voltage: 11.75 V
Temperature: 27.0 °C
KFC: 4F
KFA: 00 04
Freeze frame conditions: 21
uAdSensI_U1V2Filtered_gdu16: 1.20 V
uAdSensI_U5VFiltered_xdu16: 0.00000 V
uioUdNotFilt_xdu16: 11.91 V
uAdSensI_SwitchedKl30_xdu16: 11.91 V
ASC_CTRL_GET_ILWS_ERR_FLAGS: 00


19716 - Databus
U1123 00 [008] - Received Error Message
[New feature! Extended UDS fault detail is only supported by current gen. interfaces]
Intermittent - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 6
Reset counter: 48
Mileage: 108266 km
Date: 2021.04.29
Time: 15:15:31


Motor status: 01
System status: Driving mode
Supply voltage: 12.00 V
Temperature: 27.0 °C
KFC: 4D
KFA: 00 04
Freeze frame conditions: 21
uAdSensI_U1V2Filtered_gdu16: 1.20 V
uAdSensI_U5VFiltered_xdu16: 0.00000 V
uioUdNotFilt_xdu16: 12.08 V
uAdSensI_SwitchedKl30_xdu16: 12.06 V
ASC_CTRL_GET_ILWS_ERR_FLAGS: 00


-------------------------------------------------------------------------------
Address 55: Headlight Range (J431) Labels:| 5Q0-907-357.clb
Part No SW: 5Q0 907 357 HW: 6R0 907 357 A
Component: LWR-ECU 005 0080
Revision: -------- Serial number: --------------
Coding: 048C000009000000
Shop #: WSC 00049 770 00107
ASAM Dataset: EV_HeadlRegulVWLWRMQB 001110
ROD: EV_HeadlRegulVWLWRMQB.rod
VCID: 75E13080D4637323E0-8020


1 Fault Found:
13705985 - Databus
U1123 00 [137] - Received Error Message
[New feature! Extended UDS fault detail is only supported by current gen. interfaces]
MIL ON - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 6
Fault Frequency: 2
Reset counter: 8
Mileage: 108266 km
Date: 2021.04.29
Time: 15:09:38

Edited by Xileno on 30/04/2021 at 18:04

seat leon mk3 1.6tdi - Seat leon electrical gremlins - anyone any thought - elekie&a/c doctor
When the blower and rear wiper stop working, do the windscreen washers work ?
seat leon mk3 1.6tdi - Seat leon electrical gremlins - anyone any thought - Big John

Lot's of strange low voltage messages when operating high load devices - new battery time.

Make sure it's the correct battery for stop/start (EFB or AGM) and that it's coded in.

[Edit] - Just spotted you fitted a new battery - was it EFB OR AGM and coded in. If it was then suspect something wrong with the charging system.

By any chance did you try a battery charger - using the wrong sort with these sort of fancy battery control system can cause issues.

Edited by Big John on 04/05/2021 at 19:48

seat leon mk3 1.6tdi - Seat leon electrical gremlins - anyone any thought - Peter.N.

I would concur. Check the battery voltage with the engine running, should be around 14.4 volts - unless its one of these new fangled smart things.

seat leon mk3 1.6tdi - Seat leon electrical gremlins - anyone any thought - Rerepo

Get one of those ciggy lighter adapters with a voltmeter built in. Keep an eye on the volts as you drive around. Watch for it dipping below about 14v or above about 14.5V. Also locate and check your major earth points. Dodgy earth can cause havoc.