So this one has me scratching my head bigtime. Ive been trying to chase down an issue regarding the DSC module for almost a month now. Im getting absolutely zero communication from the DSC module, ill update the post in 30 or so minutes (depending on the time you see this) with a list of all codes that im running into, all codes are in some way related to a transmitter (dsc) receiver (FRM,SZL etc) Ive tried a few different DSC units entirely with zero communication from any of them, i do understand that the new units have to be programmed and coded to the car to match the vin and such but correct me if im wrong they should still appear as an active module right? I throw a list of what ive done below (its alot) Im genuinely looking for any type of help and im open to all ideas, Id like this to be a post where someone having similar issues can actually read through and find a solution instead of those posts that just stop.
Going onto things ive tried, starting at the basics
Ive swapped the entire unit with units we had around and/or units we bought, I do suppose the units themselves could be bad but three separate units (not including the one that was in it) aswell as the fact that there is zero communication from any of them, other modules cant find the DSC etc.
Ive gone through all fuses relating to the DSC, ontop of replacing all the fuses inside the fusebox located in the glovebox just to be on the safe side including probing the fuses for the DSC to make sure they actually were getting power and had a ground while ignition was on (Which they all do) the fuses for the specific car im working on are 26, 82 and 90.
I also checked continuity on pins 13 and 38 on the plug for the DSC itself to make sure they actually were grounded
I also jumped into unplugging certain modules that were on the same canbus line as the DCS just to see if something was causing the entire line to go crazy just to see if it brought back communication to the DSC
I checked for fluid or any traces of fluid in the foot well (Behind the left foot rest and I did find some traces of brake fluid (Which makes sense as this car has had multiple engine swaps, different transmissions etc but nothing to crazy, i do still think the brake fluid messed with a few things possibly on the harness right behind that as that runs under the carpet and connects to the YAW rate sensor under the drivers seat (I also pulled this and swapped it with another to see if that was the problem.
I eventually want to go back in there to further inspect. I did find two chewed on wires that were completely separated which happened to be the Canbus Hi and Lo wires, im assuming the little bugs i found under the rug ._.
Fixed those wires in hopes that was the reason just for it not to be.
I depinned the entire DSC connector and cleaned all the pins as they were pretty dirty from either the super corrosive brake fluid or just it being in the elements. Aswell as cleaning the both chassis side and engine side of the wiring harness on the DME as the pins on that were pretty dirty.
I know im missing a few things that i did to further investigate this DSC issue with no prevail.
I was getting into probing the Canbus Hi & Lo lines with a mulimeter and oscilloscope to see the wave lengths of the canbus line aswell as to see if the ohms were out of wack, which they were. the wave length side of things im not 100% positive on being good or bad as ive never worked on something electrical in that sense but on the ohms side of things i know i probed from the EKP, DME and the DSC to see what ohms i was getting through the system, I know the EKP isnt contributing to this as i can communicate with it and im not having any fueling issues, If im not mistaken i should be reading 60 ohms if everything is operating correctly and 120 if something is out of wack and its currently reading 120, i can go into how the readings work and what means what to further explain how this shows something is messed up. I most likely will tomorrow morning
A list of codes just so people can compare and actually get an understanding of whats going on
CD98 DSC Torque Request - Receiver DME, Transmitter DSC
CD9C Speed incorrect - Receiver DME, Transmitter DSC
CDA5 Status Receiver DME, Transmitter DSC
CD918 Wiper operation - Receiver JBE, Transmitter SZL (This is because the SZL requires the DSC to have some sort of communication as it passes through the DSC i believe)
E599 Driving speed - Receiver FRM, Transmitter DSC
E597 No message from DSC control unit - Receiver FRM, Transmitter DSC
E594 Steering angel - Receiver FRM, Transmitter SZL (I honestly cant remember if this code was here before i unplugged the column to eliminate this as a possibility of interfering
Ill update the post tomorrow morning with the remaining codes as there around 20-30 all saying the same thing, no communication from DSC to the desired module. Just not trying to get a headache yet.
Ill keep updating this post as answers come in till we hopefully find a solution, Ill put more detail in the post tomorrow morning, im just tired at this point
Ill also be extremely active on this thread, if someone is running into similar issues im more than happy to exchange ideas and things ive gone through to hopefully help you out!
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