PIT5441

Bulletin No.: PIT5441
Date: Jul-2015
Subject:
Object Detection System Message / Service Active Safety / Front Camera / Adaptive Cruise Control / Driver
Assist System DTCs U0075 U026A U026B U026C U0265 U0268 U0269 Due To MDI Or Cable Issue
Models:
2015 Cadillac Escalade Models
With Driver Assist Package RPO Y66
Condition/Concern
While performing normal diagnostics for any of the Object Detection System Message(s) below, the technician may find any of the following DTCs stored in the
active safety module: U0075, U026A, U026B, U026C, U0265, U0268, and/or U0269.
The DTCs can be history or current and when trying to communicate with any of the radars or the front camera, they may or may not communicate.
This may be the result of an issue with the MDI (Multiple Diagnostic Interface) or MDI cable that is used between scan tool and the DLC (Data Link Connector).
The Object Detection modules communicate via serial data on the object detection bus, circuits 3813 and 3811. These circuits go to the DLC at terminals 3 and
11.
The Object Detection bus is new on the Escalade models starting in 2015. Because of this, the MDI/cable may have never or rarely accessed the object
detection bus
If parts of the MDI or MDI cable that are used to access the object detection bus on DLC terminals 3 and 11 have developed an issue, it could cause these
false U-codes as well as no communication with the radars and/or front camera
This can easily mislead the technician when diagnosing any of the following Object Detection System Messages:
–
Service Active Safety Service
–
Service Front Camera System
–
Lane Departure Warning
–
Service Driver Assist
–
Rear Auto Braking
–
Service Auto Collision System
The MDI/Cable will work correctly when accessing other communications busses such as High Speed Lan (DLC terminals 6 & 14), Low Speed Lan (DLC
terminal 1), and Chassis Bus (DLC terminals 12 and 13).
Recommendation/Instructions
To determine if the MDI/cable is working correctly try using it in another Escalade with the Driver Assist Package RPO Y66, which does not have any issues.
Try to communicate with the radars, forward camera, and check the active safety module for DTCs.
If it is also setting false U-codes and the scan tool is unable to communicate with the radars and/or front camera, the MDI/Cable has an issue and needs to be
replaced or repaired.
If available, another MDI/cable can be evaluated, but remember, just because it is a different MDI/Cable does not mean that it is good. Performing the above
test on another Escalade will validate the MDI/cable is operating correctly.
If the MDI/cable was the cause of the DTCs, these DTCs are most likely false and should not be used when trying to diagnose the customer's original
complaint.
All DTCs should be cleared and the vehicle should be driven to duplicate the customer's original complaint and then a good MDI/cable should be used to check
for DTCs and perform diagnostics.
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your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.
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