Jump to content
CaddyInfo Cadillac Forum

1986 diagnostic codes


Recommended Posts

I was wondering if anyone new what these codes mean I pulled them first thing this morning I have a 1986 Cadillac Seville and the codes that came up are E047,E052,B127 and B552. Also what does the vacuum canister in the passenger side fender well due I noticed mines disconnected does it have anything to due with the brakes cause it seems like I have not that good of pressure in the pedal and does anyone have a diagram so I can put it back together any help would be greatly appreciated thanks.

Link to comment
Share on other sites

The 1992 engine codes are here and are similar to yours.

EO47 IPC -- PCM Data Problem

EO52 PCM Memory Reset

Anthony has a list of other pre-1996 OBD I codes here.

B127 .......................... PRNDL321 Sensor Circuit Problem [Park Brake Release]

B552 .................................................... BCM Memory Reset Indicator


2023 Cadillac CT4-V Blackwing

Follow me on: Twitter Instagram Youtube

Link to comment
Share on other sites

My '87 DeVille doesn't show B codes, only F....which are BCM codes. That is strange. Anyway Bruce is right. The 47 code means some communication problem between the ECM & BCM. Maybe something is disconnected/loose/contaminated/bad sensor. The 52 codes mean the battery was disconnected and the RAM was erased, meaning all the 'learned' history/drive behaviour was lost. The RAM will rebuild in time. Some disconnect the battery to clear codes, but it's usually a bad idea. When the RAM is erased, the computer control system reverts to the PROM to run everything. The ROM is based on everything being brand-new. Brand-new was 23 yrs ago.

As to the canister: that is the EECS(evaporative emission control system). It is a storage device to hold gasoline vapor when the car isn't running. It will be purged once the engine is running (if it's hooked-up). It has both electrical and vacuum-hose connections. That could be the source of the 47 code.....

The soft pedal may be caused by something as simple as old brake fluid. If the fluid is more than 5yrs old, it should be changed in the complete system. Brake fluid 'attracts' moisture and becomes less effective because moisture doesn't pressurize in hydraulic fluid and it leads to rust in the steel parts/pieces.

Do you have a Cadillac Factory Service Manual? If not, and you do your own work, get one. ebay has plenty for '86 DeVilles and start about $20. Best tool/needed tool you can have.

GM Reman 4.1 engine Dec '08

Link to comment
Share on other sites


This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Create New...