EL. POWER SYSTEM SERVICE REQUIRED with new alternator Topic is solved

altalake · Post by **altalake** » 15 Nov 2016, 02:11

Just replaced the alternator in 2001 V70 T5 - 140A unit - with an AC Delco rebuild. I know, I know, it's not a Bosch, but it's all that was available. It seems to work fine except, when I start the car, the DIM flashes the warning EL.SYSTEM SERVICE REQUIRED. When I say flash, it displays for about 1/4 second - but every time I start it. Cause for concern? Does something need to be reset with VIDA? Throwing the Delco away and buying a rebuilt Bosch for $600 is not an option.

Post by **jimmy57** » 15 Nov 2016, 07:17

Another Delco with a properly working voltage regulator is a possibility. The CEM is not liking the signal on the wire from voltage regulator. It can charge battery correctly and not have a VR that is OK for the circuit. The alternator may have the 2005 and up VR in it and could have been wrongly boxed.

Post by **oragex** » 15 Nov 2016, 10:32

I don't think it's a good idea in these electrical sensitive cars to have a so-so regulator

as above, the aftermarket regulators they put on rebuild alternators are *** Try getting a used original regulator out of ebay or scrap yard

Post by **abscate** » 15 Nov 2016, 12:09

I had my original ALT rebuilt for $200 on my 1999, as another option.

altalake · Post by **altalake** » 16 Nov 2016, 10:45

Thanks for the tips. Rebuilding wasn't an option in my case because the housing was cracked. There's also no rebuilder close by. I see IPD has the right Bosch regulator/brush set for $46USD (25% of the cost of the same thing locally) so I might just get that and put it in. The housing on this AC Delco rebuild appears to be an actual Bosch (or an exact copy) so it should fit. Sound reasonable?

Post by **oragex** » 16 Nov 2016, 13:50

They should fit, I believe. Also, if you didn't discard the old alternator, maybe just pull the regulator from it

altalake · Post by **altalake** » 27 Jan 2017, 17:45

Finally got a genuine Bosch regulator (new) and swapped it out (almost as much trouble as removing the alternator) and it worked. No more warning signal.

Post by **mrbrian200** » 01 Feb 2017, 11:18

Regulator on the Delco probably worked, but was the wrong type. Two versions: one is old school voltage 'light' signal, the other is a data connection to the CEM aka 'LIN'. Aftermarket parts are known to get the interchange wrong for specific years/models. I believe either will technically work/power the electrical system and charge the battery, but if the wrong one is installed for the vehicle configuration you'll get a charge system MIL light and/or warning message on the DIM.