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From digest.v6.n59 Tue Jan 14 14:05:28 1997
From: "Steve D'Gerolamo" <>
Date: Tue, 14 Jan 1997 08:24:51 -0500
Subject: Valeo Alternators & Electrical Troubleshooting

Some of the newer cars are coming through with Valeo rather than Bosch alternators. It will be important to know which one you have when it comes time to replace the alternator or just the voltage regulator. I've seen 3 cars in the past few months (at different shops) come in (on the back of a flatbed truck) unable to start because of an alternator failure (all 3 cars..a 525i, a 318ti and a 318i had Valeo alternators). The DME will shut down on overcharge (either spike or sustained) and the car will not run. On the 318ti, the voltage regulator was replaced and the car came back a few days later with the same problem, this time to get a new alternator. As BMW's do not come with any electrical instrumentation, its a good idea to check your battery and charging system a few times a year. With a simple voltmeter across the battery (or hot plug & chassis ground at the engine compartment for cars with batteries under the rear seat), run 3 basis tests. Cranking voltage (should be 9.5v or higher), charging voltage (13.5 - 14.5 volts with the car running) and standing voltage (around 12.5v with the engine off). The battery should also be checked for fluid level (add distilled water as needed) and if your battery is under the rear seat or in the trunk, make sure the vent tube is hooked up/plugged in properly. One last comment...if you've got a newer car (especially a 525i) and your car won't start (no cranking current), check the fusible link (80amp). BMW had a lot of problems with these and the price has come down from a few dollars to around $.75 . Keep a spare in your glove box. SD Steve D'Gerolamo c/o The Ultimate Garage, Emerson, NJ (201-262-0412)

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