Cadillac Repair Questions? Ask a Mechanic for Answers ASAP
Hello and thank you for using JustAnswer. I would like to start by asking you, do you have an analog instrument cluster or a digital cluster? I would like to send you a procedure to access any code store in the memory of the Body control module, hoping there will be a clue waiting for us. Let me know and I'll send you the procedure.
Your JA Expert,
Go through this procedure and let me know all the codes that show up.
SEGMENT CHECK The purpose of illuminating the IPC is to verify all segments of the LED displays are working. The turn signal indicators do not light during this check. Further diagnosis should not be attempted unless all segments appear, as this could lead to misdiagnosis. If any portions or segments of the IPC displays are inoperative, the IPC must be replaced.DIAGNOSTIC TROUBLE CODE (DTC) DISPLAY After diagnostics are entered, any DTCs stored in computer memory will be displayed. Each DTC consists of the system abbreviation (P - PCM, IP - IPC, AC - ACM, SD - SIR, TCS -TCS, RS - RSS, PZ - PZM, IR - IRC, RF- RFA, CC - CCP or PH -PHN), a four digit identifier, and the letter C or H. All DTCs for each system are displayed together, in consecutive order by their four digit number (lowest first - i.e. PZ 2016, PZ 2096, etc.). The final digit of the code, a "C" or an "H", is used to indicate whether the DTC is current or history. A "C" means the malfunction was still present the last time the diagnostic test was run, while "H" means the failure was not present the last time the DTC was tested for. If no DTCs are present for a system, a "NO X CODES" message (with X being the system i.e. PCM, IPC, ACM, SIR, TCS, RSS, PZM, IRC, RFA, CCP or PHN) will be displayed. If the communication line to a component is not operating, a "NO X DATA" message will be displayed, indicating that the IPC could not communicate with that system. At any time during the display of DTCs, if the "MODE" button on the IPC is pressed the system will exit "Service Mode" and go back to normal vehicle operation.SELECTING THE SYSTEM After trouble codes have been displayed, a specific vehicle system PCM, IPC, ACP, SIR, TCS, RSS may be selected for testing.The first available system will be automatically displayed (i.e. PCM?). While selecting the system to test, any of the following actions may be taken:
SELECTING THE TEST TYPE Having selected a system, the first available test type will be displayed (i.e. PCM DATA?, PCM CLEAR CODES?). While selecting a specific test type, any of the following actions may be taken:
CLEAR CODES Selection of "CLEAR CODES?" test will result in the message "CODES CLEARED" being displayed along with the selected systems name. This message will appear for 3 seconds and then return to the next available test type.EXITING DIAGNOSTIC MODE To get out of the diagnostic mode anytime during the test, depress the "MODE" or "DEFOG" button, or turn the ignition switch "OFF." Trouble codes are not erased if this is done prior to selecting "CODES CLEARED."
I'll find you everything. I have to run out for a few hours and will look everything up for you as soon as I get home. Thanks for recovering the info.
PC1520=Gear indicator problem
PC1810=Automatic Transmission Fluid Pressure Manual Valve Position Switch
IP1522=I couldn't find a definition
IP1911=Alternator L-terminal fault malfunction
PZ1558=EEPROM Checksum error
PZ1971=Inadvertent power fault
PZ2471=Interior Lamp fault
With that all said, now I'd like you to go through the procedure to clear all the codes, cycle the key off, wait a few seconds, then exit the vehicle and reenter and see if there is any change.
Patrick, at least we are making progress. All these items are controlled by the BCM, so let's cover some bases. Go to the fuse box in the trunk and make sure we have power to both sides of the fuse labeled CONVENC. It's a 20 amp fuse for the fuel door. Also in the engine compartment fuse box, check the fuse labeled: INT LIGHTS. It's a 10 amp and that's for the glove box light along with the trunk light, map lights and floor and rear lights. There are other control aspects to some of these items, but let's start by confirming 12 volts on these fuses. Let me know, also recheck the codes to see if anything came back.
You are very welcome. If you need anything, don't hesitate to ask. I'll be here for you if you need me.