Medium and Heavy Trucks

Have Truck Repair Questions? Ask an Expert

Ask an Expert,
Get an Answer ASAP!

Medium and Heavy Trucks

I have a1998 c6500 3126 cat won't start and the check engine

Customer Question
light won't come on when...
I have a1998 c6500 3126 cat won't start and the check engine light won't come on when u trun the key on
Submitted: 2 years ago.Category: Medium and Heavy Trucks
Show More
Show Less
Ask Your Own Medium and Heavy Trucks Question
Answered in 4 minutes by:
8/29/2015
Technician: Cat Man, Cat Engine Expert replied 2 years ago
Cat Man
Cat Man, Cat Engine Expert
Category: Medium and Heavy Trucks
Satisfied Customers: 9,006
Experience: I am ASE Master Truck Certified.
Verified

Thanks for asking your question and requesting me. I will try and help you out.

If the yellow check engine light does not come on when the key is turned to the on position and the engine will not start, there are only 2 things that can cause this.

The first and most common is the engine ECM is not getting the correct power and ground to function. The ECM should have power on pins 52, 53, and 70 of the rear most ECM connector. This is the truck side harness connector. 70 is the key switch wire. The grounds are on pins 65 and 67. You can remove the connector and check for power on these pins. If you do not have power on these pins, you most likely have a blown fuse in the electrical system. I would check all fuses first.

If you do have correct power and ground to the ECM, you most likely have a failed ECM. I have seen this many times over the years. To confirm the ECM is bad, you would need to install a known good ECM on the engine or you can take the ECM to the dealer to be tested. Unfortunately the ECM cannot be repaired. Replacement is the only option. I am sorry. I wish I had better news.

Please reply back if you need more help or have more questions. I am happy to assist.

Ask Your Own Medium and Heavy Trucks Question
Customer reply replied 2 years ago
Will the ecm off of a 2000 model work on this 1998 truck both c6500
Customer reply replied 2 years ago
U there
Technician: Cat Man, Cat Engine Expert replied 2 years ago

Yes it should. If you can get the the engine serial numbers off both engines in an confirm.

Ask Your Own Medium and Heavy Trucks Question
Customer reply replied 2 years ago
Ok let u no how it goes thanks
Technician: Cat Man, Cat Engine Expert replied 2 years ago

Ok sounds good. Keep me posted.

Ask Your Own Medium and Heavy Trucks Question
Customer reply replied 2 years ago
if the numbers r close will it work
Technician: Cat Man, Cat Engine Expert replied 2 years ago

As long as they are both 3126B engines. Or both 3126E engines. It will work. You just can't mix a 3126B with a 3136E.

Ask Your Own Medium and Heavy Trucks Question
Technician: Cat Man, Cat Engine Expert replied 2 years ago

Hey. I just wanted to see how things were going. Please let me know if you need more help. I am happy to assist. If my information was helpful, please leave a good or higher rating so that I receive credit. Thanks.

Ask Your Own Medium and Heavy Trucks Question
Ask Cat Man Your Own Question
Cat Man
Cat Man
Cat Man, Cat Engine Expert
Category: Medium and Heavy Trucks
Satisfied Customers: 9,006
9,006 Satisfied Customers
Experience: I am ASE Master Truck Certified.

Cat Man is online now

A new question is answered every 9 seconds

How JustAnswer works:

  • Ask an ExpertExperts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional AnswerVia email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction GuaranteeRate the answer you receive.

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... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...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:

Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help.

Mary C.Freshfield, Liverpool, UK

This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!!

AlexLos Angeles, CA

Thank you for all your help. It is nice to know that this service is here for people like myself, who need answers fast and are not sure who to consult.

GPHesperia, CA

I couldn't be more satisfied! This is the site I will always come to when I need a second opinion.

JustinKernersville, NC

Just let me say that this encounter has been entirely professional and most helpful. I liked that I could ask additional questions and get answered in a very short turn around.

EstherWoodstock, NY

Thank you so much for taking your time and knowledge to support my concerns. Not only did you answer my questions, you even took it a step further with replying with more pertinent information I needed to know.

RobinElkton, Maryland

He answered my question promptly and gave me accurate, detailed information. If all of your experts are half as good, you have a great thing going here.

DianeDallas, TX

< Previous | Next >

Meet the Experts:

Daniel Wilson

Daniel Wilson

2,139 satisfied customers

Owner at DJ Wilson

Cat Man

Cat Man

Cat Engine Expert

9,006 satisfied customers

I am ASE Master Truck Certified.

Wayne

Wayne

Journeyman

2,495 satisfied customers

worked on, Gmc, Macks, Freight liner,Mercedes Benz,,Ford, sterling

Jeremy

Jeremy

Certified Truck/Bus Technician

1,974 satisfied customers

ASE Med/HD Truck Technician, NATEF Diesel Engines and Electrical/Electronics Technician, EPA 608/609 HVAC Certified, Steering/Suspension and ABS/Brakes Technician

cumminsdr

cumminsdr

Mechanic

1,195 satisfied customers

All types of Cummins applications

Curtis B.

Curtis B.

Technician

770 satisfied customers

Technician turned service manager on multiple lines of trucks and engines, used in industry.

dieseldan55

dieseldan55

Contractor

74 satisfied customers

Road Service mechanic for Volvo Construction.

< Previous | Next >

Related Medium and Heavy Trucks Questions
I'm a new operator. How do you turn on a liebherr tower
I'm a new operator. How do you turn on a liebherr tower crane and also weathervane it ? … read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
2,139 satisfied customers
How many hours on my D6R cat can i expect to run without
how many hours on my D6R cat can i expect to run without engine transmission and undercarriage overhaul … read more
catmastertech
catmastertech
Field service technician
Vocational, Technical or Trade Scho
1,287 satisfied customers
My E350 van has a lot of heat and unwanted air coming in
Hello, my E350 van has a lot of heat and unwanted air coming in around the passenger feet area. Even when the vent is off lots of air, sometimes smelling slighlty of exhaust is coming in. The origin s… read more
Pete
Pete
Independent Auto Technician
Vocational, Technical or Trade Scho
138 satisfied customers
Dertoit 14 frighliner 2005. I changed ecu fuse, restart with
I changed ecu fuse , restart with take off negative from battery … read more
spankyjr1
spankyjr1
Retired
Vocational, Technical or Trade Scho
19 satisfied customers
2009 freightliner Detroit 60 14L. Throwing fault code ECU
2009 freightliner Detroit 60 14L. Throwing fault code ECU 128 SID 154 Fail 00. I cant figure out what code this is.… read more
Wayne
Wayne
Journeyman
Vocational, Technical or Trade Scho
2,495 satisfied customers
I HAVE A 2015 Freightliner cascadia DD15 with a headache
I HAVE A 2015 Freightliner cascadia DD15 with a headache code 5246 FMI 15 … read more
roy
roy
Associate Degree
3 satisfied customers
I have frightlinet detroit series 60 chck engin light on eng
I have frightlinet detroit series 60 chck engin light on cod eng sht hi 128 351 00 and eng sh hi 128 351 03 … read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
2,139 satisfied customers
09 Isuzu F Series Medium Duty A/C compressor will not
09 Isuzu F Series Medium Duty A/C compressor will not engage. … read more
Andy3221
Andy3221
truck /coach technician
Vocational, Technical or Trade Scho
222 satisfied customers
Need to set injector pump timing while pump is installed.
Need to set injector pump timing while pump is installed … read more
FIX-IT
FIX-IT
Comercial transport technician
Vocational, Technical or Trade Scho
784 satisfied customers
Getting a 12 8 code. Seemed to Have lack of power. Smoke,
Getting a 12 8 code. Seemed to Have lack of power. Smoke, maybe coolant burning coming out of ac vents, Stop Engine light comes on if a wait a few minutes any try to drive away. Water temp seems to be… read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
2,139 satisfied customers
I HAVE COOLANT GETTING INTO OIL ENGINE REBUILT 50,000. MILES
I HAVE COOLANT GETTING INTO OIL ENGINE REBUILT 50,000. MILES AGO WHAT IS CAUSE? … read more
Curtis B.
Curtis B.
Technician
Associate Degree
770 satisfied customers
We have a 2004 freightliner schoolbus. something is going on
we have a 2004 thomas freightliner schoolbus. something is going on with our tail lights. they suddenly stopped working... … read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
2,139 satisfied customers
2009 Peterbilt with isx Cummins on insite trying to do a
2009 Peterbilt with isx Cummins on insite trying to do a stationary regen says clutch pedal is depressed just put in new clutch switch still says depressed try to bypass with jumper wire still says de… read more
FIX-IT
FIX-IT
Comercial transport technician
Vocational, Technical or Trade Scho
784 satisfied customers
Will turn but will not fire. 2006 Mack Granite with AMI_370
will turn but will not fire. 2006 Mack Granite with AMI_370 engine. … read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
2,139 satisfied customers
It turns over but doesn't crank warn engine light flashing
It turns over but doesn't crank warn engine light flashing very fast … read more
Wayne
Wayne
Journeyman
Vocational, Technical or Trade Scho
2,495 satisfied customers
2009 freightliner century with Detroit 60 series. I have a
2009 freightliner century with Detroit 60 series. I have a basic scanner and scanned what the check engine light was and the code came up (003662 14 spn). What can this be?… read more
Wayne
Wayne
Journeyman
Vocational, Technical or Trade Scho
2,495 satisfied customers
My Rv shut down codes are SPN627 and FN12. I am not sure I
I have not tried anything except trying to start engine just trying to determine where to take it for repairs … read more
cumminsdr
cumminsdr
Mechanic
High School or GED
1,195 satisfied customers
I am getting DPF fuel pressure voltage and EGR delta
I am getting DPF fuel pressure voltage and EGR delta pressure and fuel delivery pressure codes on a 2012 pack at motor … read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
2,139 satisfied customers
Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Show MoreShow Less

Ask Your Question

x