[OttoFix]

1990 525i with PPPP error code. Symptoms: erratic tachometer, fuel and temp gauges not working, rough idle, and, more recently, battery dies overnight.

May have been precipitated by other fault; intermittent power window and wiper failures tracked down to positive cable junction (loose connections) about a foot from the battery. Well intentioned mechanics did some trouble shooting under the back seat and possible inside the dash, behind the radio. (Not a factory radio, but radio has been in there a year without problems.) Mechanics' work may well be unrelated to present problem.

Noticed something in the Haynes repair manual about the SI board and batteries that may be pertinent.

Apologies if this has been addressed in a previous thread, I looked and couldn't find anything.

Thanks