How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Mike S. Your Own Question
Mike S.
Mike S., ASE Certified Technician
Category: Cadillac
Satisfied Customers: 7433
Experience:  ASE certified
Type Your Cadillac Question Here...
Mike S. is online now
A new question is answered every 9 seconds

I have a 98 Cadillac Deville that has a slow battery drain

This answer was rated:

I have a 98 Cadillac Deville that has a slow battery drain on the Body 3 circuit. Based on the schematics, there are 2 relays in that circuit. Can you tell me where these are located? If I leave the car sit for several days the battery will be drained. I have unplugged all circuits and put an ampmeter on the body 3 circuit and see that it fluctuates from what specs are calling. I just suspect it is the relays and want to replace them to see if this stops my drain. Thanks.
There is a micro relay center in the trunk. For that diagram, click here and here.
Mike S. and 2 other Cadillac Specialists are ready to help you

For the Trunk compartment fuse panel locations—1996–98 Deville, click here.

There are three fuse blocks in most late model Cadillacs: the engine compartment fuse block, the MaxiFuse relay center and the rear compartment fuse block.All Devilles and Fleetwoods are equipped with a fuse block located under the left-hand side of the instrument panel. In addition, 1991–93 Deville and Fleetwood are equipped with a fuse block located in the rear of the engine compartment.

Customer: replied 7 years ago.
Is there a particular one that has been a problem historically? I have the back seat out and right now trying to take amp readings on body3 circuit. Of course it isn't doing anything right now.
This is tsb explains was is allowed as a Battery Parasitic Drain, as a rule of thumb, maximum parasitic drain is around 30 mA (0.030 amp). Click here. What I would do is with the fuse in look for anything on that circuit that doesn't work and find out why, possibly a short to ground on the wire or look for anything remaining on such as a bulb. Anything with a memory will draw a small amount, such as radio presets, the ecm memory and a clock.
Customer: replied 7 years ago.
Thanks. I took all 3 grounds loose back there and made sure that they were clean. There were a few relays loose from their mounts so I got them back as well. So far I can't seem to get it to draw extra again. I'll see if it still does it. Thanks for your help.