Mercury Repair Questions? Ask a Mechanic for Answers ASAP
Hi there. There are no TSBs for the PCM with the exception of one for proper re programming of the pcm, which I can forward to you if you would like. The PCM is definitely a possibility however There is a diagnostic procedure for the symptoms that you are describing. The first step is to check for any diagnostic trouble codes. If any were stored, I imagine they would have indicated that in your paper work? I assume they did not encounter a code, but if they did please let me know.
Second, please check the 10 amp fuse in position 2 in the battery junction box while the engine running. have somebody monitor the charging system warning light while you push on and wiggle that fuse and see if that light flickers while you are doing that. It is common to have a bad connection in the battery junction box at that fuse causing the exact symptoms that you are experiencing. Please let me know how that goes and we will take it from there.