1998 Cadillac DeVal error code u1255 - 1998 Cadillac DeVille

U1255 Lost Communications

When a malfunction such as an open fuse to a module occurs while modules are communicating, a DTC U1001-1254 Loss of 000 Communications is set current. When the modules stop communicating the current DTC U1001-1254 Loss of 000 Communications is cleared but the history DTC remains. When the modules begin to communicate again, the module with the open fuse will not be learned by the other modules so U1000 or U1255 is set current by the other modules. If the malfunction occurs when the modules are not communicating, only U1000 or U1255 is set. Radio quit working shows Code IRC U1000 please help

OBDII Code U1255 CADILLAC Lost Communications HelpForCars net P1610 Cadillac how to repair
DTC B1348 Very Low A/C Refrigerant Pressure
DTC U1255 Serial Data Line Malfunction
The class 2 serial data line communicates information between the modules. Each module connected to the serial data line is assigned a recognition code, or address. This code is used in order to identify which modules are communicating. Modules communicate with each other by periodically sending state of health (SOH) messages. When the ignition switch is in RUN, each module that is communicating on the serial data line sends an SOH message every 2 seconds. This ensures that the system is operating properly. At key on, most modules must learns the initiation data from other modules on the serial data line. When a module requests initialization data from another module, and that request is not acknowledged after 5 seconds, the module stores class 2 initialization error DTC U1255.
Conditions for Setting the DTC
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The module does not receive required initialization data on the class 2 serial data line. The module retries the request for 5 seconds, and then sets DTC U1255.

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This DTC only sets if DTC U1300 or U1301 are not current

Attempt to establish communication with all of the modules using a scan tool.
Does the scan tool communicate with all of the modules?
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Go to Step 3
Go to the appropriate diagnostic system check for the module that is not communicating

Go to www.obd-codes.com and look them up please.

Reset error codes by disconnecting battery for 5 minutes. Start fresh. all codes should be clear now. drive and see if any new codes come on. They are the ones you need to address.

These two error codes may be related. The p1601 is saying that the internal temperature of the power control module PCM is too high or that the outside temperature is out side of normal range. The second code u1255 is set when control modules fail to send the right signals to one another. If the PCM is malfunctioning due to high temperature or error then this may cause the lack of data transfer and hence the u1255 signal. Disconnect the negative terminal to the battery. Check out the PCM, ensure that all electrical connections to it are clean and secure; a poor connection can generate quite a lot of heat hence the p1601. Ensure that there is no sign of wires shorting underneath the PCM. If all connections look clean and free of corrosion open up the PCM and look for obvious hot spots on the main board. A dry joint or annular crack in the solder around a power pin on the board can create heat. If you see this just re-solder. If the board is cooked beyond repair then a new PCM is needed. Ensure that the PCM is shielded from direct sources of heat such as the exhaust manifold etc. When the battery is reconnected the error codes most likely will have been cleared but if the problem persists the error codes will be logged again.

Replaced digital dash on 1998 Cadillac DeVille. Receiving error message 'Starter disabled keyless remote' 'Wait 3 min.' After 3 min, car still doen't start.

This code means there has been excessive slip in the transmission, possibly due to lack of fluid.

Check the fluid level by warming up the car then check the dipstick with the engine still running.

Or....you may have a faulty vehicle speed sensor (VSS) located on the output shaft transmission casing.

U1255 - Class 2 Communication Malfunction (Serial Data Line Malfunction)

here is a link to all of the codes for your caddy
http://myweb.accessus.net/~090/dtcobd2n.html#net

sounds like a bad computer or electrical problem use a test light to see if you get power to and of the wires on the computer