W210 E55 Fried diagnostic module

[JulianFDRacing]

I had some issues trying to connect up an OBD2 port into my W210 E55 project and I have a feeling I connected wrong pins to power (albeit only for a second). If I now try to use a proper 38pin to OBD2 converter it cannot pick up anything using an ELM327 that did work before I cocked up, car wont turn over but was having issues before I started messing with the OBD2 port. Key seems to work and steering column unlocks. Using a Carsoft Multiplexor returns a load of codes but wont pick up SAM or ECU modules (its doesn't on my W211 either but that's another thread )

I don't know if I have fried the ECU by 'maybe' connecting a power to the ECU diag pin but I stripped the ECU and no signs of anything burnt out (I have photos). I've replaced the SAM module due to water ingress and the K6 relay module just because they are always suspect but its made no difference and I get the same codes and no SAM (I can hear relays, I think 1 in K6 in acc and then in SAM when turning on ignition (thinks its small green one). The car is still in bits being welded so don't want to put the fuel pump back in but think I need to do so just to see if the ECU is sending a signal to it to run. The air pump does run for a couple of minutes when the ignition is turned on.

I also connected a voltmeter to the radiator fan and it wasn't showing a voltage with the ignition on but the little ECU cooler was running (is that a sign the ECU is alive?)

I've been over all the earths and main feeds into everything and all tested good but below are the codes I do get, bare in mind that its essentially just the engine/gearbox/dashboard in the car so I expect lights/brakes etc to be whinging

Can anyone point to anything in the WIS or online that can help me troubleshoot, I have a working WIS but trying to make use of it is difficult (I am definitely a WIStard)

Single diagnosis Traction - Status: ERROR !
C1140 Steering angle sensor, Open-circuit/short-circuit, initialisation
C1332 BAS solenoid valve, open-circuit/short-circuit
C1120 ESP yaw rate sensor or Micro mechanical turn rate and steering angle sensor : Open-circuit/short-circuit in cables for turn rate signal
C1022 CAN communication with ECM control module or CDI control module disrupted
Single diagnosis AIRBAG - Status: ERROR !
B1315 Seat ocupantie-, children seat recognition : passenger seat
B1859 Driver Airbag squib ignition circuit R12/3 : resistance to high
B1861 Passenger Airbag squib ignition circuit
B1863 Driver emergency tensioning retractor squib ignition circuit
B1864 Front passenger emergency tensioning retractor squib ignition circuit
B1865 Rear left emergency tensioning retractor squib ignition circuit
B1866 Right rear emergency tensioning retractor squib ignition circuit
F146
B1755 Serial Port K2 from the KLA/TAU panel with the instrument cluster : open circuit
B1473 Coolant level control switch S41 or Clean water level switch S42 -> Open circuit
Single diagnosis EGS - Status: ERROR !
136 Communication with Kombi Instrument disturbed
HRA Single Diagnosis HRA - Status:

 

[bob6600]

Are these codes before or after your issue?

Do you have power to the 38 pin? Pins 1 and 3 I think...one is ignition live. There is a fuse (on the diesels) which powers this but is linked to the flap motor, not sure on the AMG

 

[JulianFDRacing]

Before the issue I only had the Elm327 scanner working via bodged wiring and the starter working intermittently, it was whilst trying to do a neater job of the wiring that this happened, the Elm327 stopping and the starter not operating at all set me off buying the K6, SAM (tried original and new actual SAM plug in module rather than fuse/relay box) and multiplexor so I could try and troubleshoot. I do find it odd that the multiplexor only picks up two modules on the W211 I have but 5 on the W210 with it all broken

I'll check the pins you suggested but not at moment as its dark, throwing it down and the car is under a tarp I can assume they do work as the Elm module(s) get power and the Multiplexor does work to a degree, they get power with the ignition off so can at least assume the perm live is connected, fuses have ALL been checked with a tester and the live rails are getting power to the fuses as expected with the ignition on. I've been over every contact with contact cleaner several times and checked I've not cut any cables that didn't start out cut before this drama started. I have tried a number of batteries and the original is still OK, I have a battery tester connected most of the time I'm testing and have a proper battery charger (boris) to keep it topped up. I don't think the ECU box fan will run unless the ignition is on and it does work with the ignition on. Is there a way to operate the starter without it being through the key, there isn't a relay I can bridge from what I can see (correct me if I am wrong please)

Given that the power is there where does the wire from the ODB2 pin go to, on the WIS I found a wiring diagram that said it connects to the "diagnostic" module but it doesn't actually have a separate module so assume its part of the ECU.

 

[JulianFDRacing]

I ended up buying a new ECU and swapping the DAS ID chip over, ECU is now alive but has an E430 map on it, just read it earlier with a Galetto and need to either bench read the old ECU (with no ID chip) or desolder it and maybe read like that (or just solder in new ECU as last choice)