[bmwloverx]

I have n55 engine. Is ibs causing lin problem and then messes up water pump or water pump causing ling problem and messes up
ibs? Please check attached picture.



I cleared errors. Removed ibs, drove 10 miles problem not came back. Connected ibs back, drove again 20 miles, no errors.

I tested car with ista because water pump was turning on itself after turning off engine.

P.s.
I did bleed from ista. Water pump speed was 30-200. Ista gave these numbers.

[bmwloverx]

No experience?

[thebmw]

I thought you were talking about IBS and water problems in regards to the bowel and the bladder problems. I could have helped you there. Can't help you with your car issue though.

[vt100]

How old is the water pump? Considering it's N55 and if it's older than 50kmiles I'd replace it just to be on the safe side.

[bmwloverx]

Originally Posted by vt100

How old is the water pump? Considering it's N55 and if it's older than 50kmiles I'd replace it just to be on the safe side.

On another n55 it lasted 130000 miles. So change after 50000 miles it is wasting money. People usually kill them because of bad battery.

[bmwloverx]

Originally Posted by thebmw

I thought you were talking about IBS and water problems in regards to the bowel and the bladder problems. I could have helped you there. Can't help you with your car issue though.

Where to laugh?

[RockCrusher]

Originally Posted by bmwloverx

I have n55 engine. Is ibs causing lin problem and then messes up water pump or water pump causing ling problem and messes up
ibs? Please check attached picture.



I cleared errors. Removed ibs, drove 10 miles problem not came back. Connected ibs back, drove again 20 miles, no errors.

I tested car with ista because water pump was turning on itself after turning off engine.

P.s.
I did bleed from ista. Water pump speed was 30-200. Ista gave these numbers.

Below is what I found at:

https://bmwfault.codes/

I'll post some more info but the site has possible different info depending upon the car's ECU variant.

So for the most applicable info you need to use the fault codes search and then read the details under your car's ECU variant.

20A701
Diagnosis monitors the speed of the coolant pump.
The fault is detected when the deviation of the actual speed from the target speed exceeds the limit value.

Possible cause of fault:
- Air in system
- Coolant contaminated or incorrect mixture ratio
- Wiring harness defective
- Coolant pump defective

Service Plan:

- Vent system
- Check coolant (foreign bodies, mixture ratio, viscosity)
- Check wiring harness
- Replace coolant pump


213601
The diagnosis monitors the standby current.
The fault is detected if the standby current exceeds the threshold value of 80 mA.
Possible fault cause:
An additional retrofitted power consumer (e.g. hands-free system, navigation device, device for enabling the TV function when the vehicle is in motion, cooler box, rodent repelling device, etc.) is connected to terminal 30, terminal 30F or directly to the battery.A component or a control unit is consuming too much current during the rest state (corroded connector, short circuit or internal fault).


801709
Rear-lid-lift motor, left: open circuit
Control unit: HKL
Function: Automatic luggage compartment lid actuation
Component: Trunk lid lifting drive, left
A line disconnection has been detected or the left automatic tailgate drive is faulty.
Following an adjustment request, one of the two lines for the left automatic tailgate drive is disconnected or the voltage supply of the HKL control unit (load circuit, terminal 30) is faulty.

Service Plan:
Carry out functional check.Check voltage supply (terminal 30)Check wires and plug connectionsCheck left automatic tailgate drive.


8040B1
Wake-up line to the intelligent battery sensor IBS: Short circuit to B+ or line disconnection

Diagnosis monitors the wake-up line between the front electronics module (FEM) and intelligent battery sensor (IBS).
The fault is detected whenever there is a short to B+ or an open circuit on the wake-up line (LIN bus).
Fault Code Conditions
General Conditions

Service Plan:
Check wires and plug connections between FEM and IBS and repair if necessary.If the wires and plug connections are OK, then check bus connections for all other LIN partners and repair, if necessary.


8040BD
Reset or deactivation of terminal 30F
Diagnosis monitors the control of terminal 30F.
The fault is entered in the following two cases:
When terminal 30F is reset or switched off.When a reset or switch-off of terminal 30F is requested but does not take place due a switch-off inhibitor.
Following switch-off inhibitors are possible:
Parking light, parking lights or hazard flashing ON.Terminal 30B ONRelay fault in power electric windows.


Service Plan:
Carry out following test module (ABL): Energy diagnosis.
The aim of energy diagnosis is to find the possible fault causes that have resulted in a reset or deactivation of terminal 30F.


CD8E10
LIN bus : Communication fault

Diagnosis monitors the LIN/BSD bus communication.
The fault is detected when communication is not possible between all bus users.

Service Plan:
- Disconnect the bus users one after another. Read out fault memory. If the fault does not presently exist, the disconnected user / partial wiring harness is causing the malfunction on the bus. At least one user must always remain connected; otherwise, the fault will be entered again.
- Check voltage supply to the bus user.
- Check the wiring harness between the DME and bus user. For this purpose, all bus users must be disconnected.
- Replace bus user


CD8F01
LIN, message; intelligent battery sensor (IBS): Missing

Diagnosis monitors the LIN/BSD bus communication.
The fault is detected when the LIN/BSD message is not received within 90 s.

Service Plan:
If additional faults related to the LIN/BSD bus communication are entered, then remedy these first. When multiple message faults for the LIN/BSD bus are stored by different bus users, check the corresponding wiring harness / bus user. Check voltage supply to the bus user. Check wiring harness between the engine control unit and bus user. Replace bus user.


CD9010
LIN, message; electric coolant pump: Missing

Diagnosis monitors the LIN bus communication of the electric coolant pump.
Fault monitoring conditions:
The fault is detected when LIN-bus communication with the coolant pump is disrupted.

- Check the LIN wiring and plug connections.
- Check the wiring harness of the coolant pump.
- Check the coolant pump with the diagnostic system.
‐ Renew coolant pump.


Ok. I have to underscore I don't know the ECU variant of your vehicle.

I picked the first ECU variant when pasting the info here.

A common theme in all of the above is "water pump". Would I throw a water pump at the problem? Well maybe. But maybe not.

I would hazard a guess a tech would first check battery voltage, battery connections.

I see directions to check wiring/connections.

Furthermore I don't know the car's history but whenever I see a number of recommendations to check wiring/connections the old rodent has been at the wiring dread comes to mind.

So a thorough check of the wiring/connections at the areas designated above and just general wiring for rodent damage is advised.

While the tech probably has seen cars in with similar list of codes he would at least take some basic steps to ensure it it not battery/battery connection or wiring/connection problem before throwing a water pump or a new IBS module or whatever controller might be suspect based on the error codes/ECU variant at the codes/symptoms.