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 Virtual Technician Your Own Question
Virtual Technician
Virtual Technician , ASE Certified Technician
Category: Car
Satisfied Customers: 96
Experience:  25 years Experience. All makes and models, Shop Owner, Access to 4 repair databases. - I take the Opt Out Questions :)
Type Your Car Question Here...
Virtual Technician is online now
A new question is answered every 9 seconds

Mazda B2500: 1998 mazda B2500 battery keeps draining caused

This answer was rated:

1998 mazda B2500 battery keeps draining caused by fuse # XXXXX in the I/P. Pulling .45 amps when I connect the battery. Description on fuse legend is "GEM/CTM, Instrument cluster". I can't find this circuit in the owner's manual or a Haynes. Any idea how to further investigate and what the wiring diagram looks like? Any help would be greatly appreciated. Need for work on Monday!
Hi, I'm a Moderator for this topic. I've been working hard to find a Professional to assist you right away, but sometimes finding the right Professional can take a little longer than expected.

I wonder whether you're ok with continuing to wait for an answer. If you are, please let me know and I will continue my search. If not, feel free to let me know and I will cancel this question for you. Thank you!

Hi my name is XXXXX XXXXX I'll try my best to help with your vehicle issue.

***Please note: Not every answer I give you is something you were hoping to hear, even though it is true.
Such as; (it's more expensive than you wanted to spend, or you will need to have a professional repair shop do the diagnostics and /or repairs due to complexity reasons).

Here is a diagram to the BCM:


1. Do you have any warning lights on when vehicle is running?

2. Do you have a scanner capable of getting into the Body Control Module?

Here is the wiring to the cluster (gem module):


As you can see - when the power goes into the module(s) - it is dispersed FROM it to LOTS of items.

It could be a bad BCM, GEM module, or cluster and will take some time to track everything down.

Do you have a digital multimeter?


Is there ANYTHING else that is not functioning correctly?

Customer: replied 3 years ago.

Yes, I do have a digital meter. I may have a buddy that has a scanner for the BCM which would probably be the most valuable troubleshooting I could do. I will check with him tomorrow.


1. The warning flashers stay on when the battery is connected. I used to be able to push the theft deterent button to turn off the flashers but this does not work. I would like to permently disconnect the theft deterent but do not know how. Any suggestions on where to start?

2. Is it correct to say since I do not have electric windows I have a BCM instead of a GEM?


3. I have a strong background in electronics and controls troubleshooting. The images you sent will be a big help but since I do not see a way to isolate each CTM output I will probably need a full set of wiring diagrams to get much further. Any further tips or guesses on the most likely items?

I just thought of something - when are you checking the draw from fuse 25?

Here's why I ask:

Most 1995 and newer Ford/Mazda products have modules in them which will remain in "standby" mode for a period of time after the vehicle is shut off. While in this mode, they will draw current which is excessive by established standards for normal current drain. However, after no longer than 1 hour of inactivity (no change in state of door switches, door handle switches, hood switch, trunk/tailgate switch, ignition switch or key-in-ignition switch), they should go to sleep, and total current draw should be less than 50 mA.


Before we head down a wrong path

1. Fully charge the battery

2. Hook up meter as described in next test - make sure it's visible from inside the vehicle

3, Locate and Pull all fuse covers inside vehicle

4. Go to the restroom

5. Then grab a flashlight,

6. Get a good book, (you're going to be inside the truck for a while)

7. You'll need needle nose pliers and perform the following test:


MY summary of the issue - please correct me if I am wrong.~~~~~~~~
Vehicle Application:
1999 Ranger 2.5 / B2500
Customer Concern:Electrical drain causing the battery to go dead. When pulling fuse #25 (7.5 amp) from the interior fuse box the drain goes away.
Tests/Procedures:1. Install an ammeter between the battery negative post and cable to identify the amount of amperage draw that is present on the vehicle. A normal draw will indicate approximately 250 milliamps (mA) for 45-60 minutes after all doors are closed with the ignition switch off. After that time frame, the Generic Electronic Module (GEM) will enter a sleep mode and the total vehicle drain should decrease to indicate 50 mA or less.

2. If the amperage draw is normal when initially turning the ignition switch off with the doors closed, but it stays close to 250 mA after the 60 minute wait period, remove fuse #25 to see if the mA draw drops to less than 50 mA indicating a defective GEM.

3. If the draw is higher than either of the normal specification values, start pulling all interior fuse box fuses one at a time until the draw drops under an acceptable level to determine the circuit and components which are influencing the excessive draw. Leave the fuses out as they are pulled to prevent awakening any modules which could result in falsified readings.

4. If all interior fuse box fuses are removed and the draw is still excessive, start removing the under hood fuses one at a time until the drain drops to an acceptable level to identify the circuit of concern. Again leave the fuses out as they are pulled to prevent waking up any on-board module.

5. Once the fuse of concern has been identified, reinstall the fuse and start disconnecting all related components of that circuit to identify if the draw is related to a component issue or a circuit problem.
Virtual Technician, ASE Certified Technician
Category: Car
Satisfied Customers: 96
Experience: 25 years Experience. All makes and models, Shop Owner, Access to 4 repair databases. - I take the Opt Out Questions :)
Virtual Technician and 5 other Car Specialists are ready to help you

Thank you for the positive feedback :)
I'm glad we got it figured out.
Part of the reason I decided to participate in this forum was not only to help people on here but also to further my knowledge for my own shop here in WI.

I would be interested in knowing what you found out from the testing I sent you as to what the issue ended up being.

Thank you in advance for taking the time to tell me so that I may also help others.

JustAnswer in the News:

Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.

What Customers are Saying:

  • I would (and have) recommend your site to others I was quite satisfied with the quality of the information received, the professional with whom I interacted, and the quick response time. Thanks, and be sure that I'll be back whenever I need a question answered in a hurry. Stephanie P Elm City, NC
< Previous | Next >
  • I would (and have) recommend your site to others I was quite satisfied with the quality of the information received, the professional with whom I interacted, and the quick response time. Thanks, and be sure that I'll be back whenever I need a question answered in a hurry. Stephanie P Elm City, NC
  • used your service this weekend with "Trecers" help. thank you ,thank you, thank you. replaced an A/C fan motor. Local Auto Zone had part. $15.00 "tracer" fee and $40.00 for parts, I saved several hundreds of dollers at a shop. i will recommend you and use you in the future. David L. Richmond, TX
  • 9 dollars, 2 hours of my time, and I drove away. Your diagnosis was right on the mark. Thank you so much. Phil Marysville, CA
  • Lurch. Thank you very much. I had real doubts about this website but your promptness of response, quick followup and to the point answer with picture was incredible. Charles Walnut Creek, CA
  • As a single woman, I really appreciate an excellent and affordable opinion.
    Thank you Geordie, I will not hesitate to contact justanswer in the future!
    Sue Charleston, WV
  • Another great insight to what may be the problem. I will have my mechanic take a look at it tomorrow. Thanks again, do indeed know your stuff. Jim Castleberry, FL
  • Excellent reply, and also very quick. Really sounds like the Expert knows what he is talking about. I will be back to use your service when I need more help with my RV. Dutch USA

Meet The Experts:

  • Chris (aka-Moose)

    Chris (aka-Moose)


    Satisfied Customers:

    16 years of experience
< Last | Next >
  • Chris (aka-Moose)'s Avatar

    Chris (aka-Moose)


    Satisfied Customers:

    16 years of experience
  • Ted G.'s Avatar

    Ted G.

    ASE Certified Technician

    Satisfied Customers:

    20 years auto repair experience, ASE Master Tech, Mechanical Failure consultant, Expert Witness
  • George H.'s Avatar

    George H.

    ASE Certified Technician

    Satisfied Customers:

    ASE Master Tech 15+ yrs, AAS Automotive Technology, Factory trained Asian specialist
  • GM Tech (Cam)'s Avatar

    GM Tech (Cam)

    Auto Service Tech

    Satisfied Customers:

    GM Grand Master Technician 2007. 14 years experience.
  • Amedee's Avatar


    Former ASE Master Tech

    Satisfied Customers:

    ASE certified tech advanced level specialist. Wisconsin certified emissions state inspector
  • Jerry's Avatar


    Master Mechanic

    Satisfied Customers:

    ASE master, 30+ years. All makes and models. Trouble shooter, shop forman, service manager
  • Richard's Avatar


    ASE Certified Technician

    Satisfied Customers:

    12 years Ford Lincoln/Mercury Jaguar dealership as a technician and shop foreman reparing all makes