New owner of an e53 4.8is with issues :)

[andrewwynn]

Abs errors will not cause failsafe but TC errors will


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[Peezen]

Ok gotcha. As a side question, the car goes into limp mode but there is no indication on the dash, and no codes when read. It resets on start up.

Back to the issue at hand. If the code reader seems to be able to connect just fine with the TC module and the servotronic, could it be a faulty actuator that’s causing the problem?

The only code I’m getting is for the oil wear, but that has been changed. Perhaps the new actuator needs to be calibrated?

All of the connectors look to be in good condition going from the actuator to the module.

[wpoll]

Originally Posted by Peezen

... The only code I’m getting is for the oil wear, but that has been changed. Perhaps the new actuator needs to be calibrated? ...

Not sure about calibrating a new actualtor but the whole transfer case needs re-calibration after a fluid change - I used DIS but you can also use ISTA-D and (I think) some Foxwell units.

[Peezen]

Would the oil wear issue and code be enough to set off the trifecta lights and throw the car into limp mode after a short drive?

[wpoll]

Originally Posted by Peezen

Would the oil wear issue and code be enough to set off the trifecta lights and throw the car into limp mode after a short drive?

While I'm very tempted to state "NO", I'll go with "probably not".

[Peezen]

Ok, so A few things.:

after reading a bit more I am wondering if the vehicle is actually going into official limp mode. I will be driving and all of a sudden there is no power when I push the gas. Just revs and no acceleration. There is no indication on the cluster, thought it still reads SLS inactive. and chimes for lights out. It’s seems like I can only drive very slowly and if left I may even grind to a halt. Very disturbing.

I have scanned the codes with Schwaben tool, CReader, and INPA, and none come back with any codes mentioning limp mode. The only transmission codes that come up have to do with not getting messages from the TC. There are no codes from the engines at all.

The TC throws a code for oil wear (replaced today), and messages about not getting messages from the DSC module, and the ABS module is throwing codes for a faulty front left wheel sensor, and about not getting messages from the TC.

Can the abrupt loss of power be related to these three modules not being able to communicate with each other, but also not throw a code? When I turn the truck off and on again, even while moving, it drives and accelerates like normal, nice and smooth, and powerful, until ‘randomly’ I get an abrupt power loss.

Does this sound like a voltage issue? I have a brand new battery, and the trunk well was at one point filled with water, enough to destroy the radio, and the battery area had a ton of corrosion from the old battery. Could the alternator or the ground straps cause this kind of issue? The carpet on the rear driver side is completely saturated, like a sponge, though the TC wires look fine.

The random power loss is my biggest concern right now as I would like to be able to drive the truck.

[andrewwynn]

I don't think your engine is going limp mode on think your transmission is confused.

Can you watch your egs solenoid pressures real-time? I think your xm is failing to shift giving you revs with no acceleration

I had similar issues when my xm connector got filled with water and I even had bad shifting before I got xm limp mode.

If engine goes limp you won't have revs it will have low rev no accelerating like if stuck in 4th gear.

Have you tried m/s to override the gear?


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[EODguy]

Check both potentiometers in the accelerator pedal as it could be screwed up enough to not give the range of throttle. (Scanner will show %)

Don't forget to reset the oil wear indicator on the TC.... ask me how I know

Interlock cable in mechatronic gearshift good?


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[E53Envyy]

When I was diagnosing a driveline pop I disconnected the transfer case actuator multiple times. After doing so I only had the 4x4 light and never went into limp mode (and I was driving the x hard). It turned out to be the chain inside the case was slipping so I had to completely swap the case. Only the two connectors (actuator and sensor) connect to the transfer case and my 2005 4.4 uses the same TC.

Note: when the x5 is turned off the transfer case completely disengages the front wheels. In my situation I knew that my actuator was working and I only disconnected it will the car was off as my goal was to eliminate the front driveline as a possible suspect of the poping noise. You mentioned that you can test and hear the actuator which is good, but another test you can do is jack up the front of the car and confirm the front wheels spin freely. Furthermore, try disconnecting the actuator as maybe the aftermarket actuator is somehow related to the communication issue (far fetched but worth a try).

Not seeing any lights on the dash in limp mode is strange. Usually the “cog of death” or EML is associated with limp mode. While in limp mode have you tried shifting the tranny manually in sport mode?


Cheers, E53Envyy


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[Peezen]

Ok, lots to do today, I will report back.

One last thing, I have tried to do the oil wear reset on the TC but it says that it fails every time.

Also, what is production mode? That is off as well as transport mode for the sled levelling air ride.