Medium and Heavy Trucks

Have truck repair questions? Ask an Expert

Connect one-on-one with {0} who will answer your question

I have a 97 Peterbilt 378. I had some welding done in the…

Customer Question
I have a 97 Peterbilt...
I have a 97 Peterbilt 378. I had some welding done in the frame yesterday and the truck ran fine today. While driving today, I noticed my engine brake would only work when I pressed the brake pedal, as it though the cruise control was on. With the cruise control on/off switch in the off position, the cruise was still working like it was stuck on. The dash light does go on and off with the switch. I unplugged the switch with no luck. Now is where things get weird. While seeing if the cruise turned off, I'd rev the engine up and see if the jakes were working. After doing it two or three times the truck shut off and will not restart. I have no check engine light, to me meaning no communication with the ecm. I checked for power and ground on the ecm 40 pin. Had a corroded wire for the battery event recorder, fixed that and it still wouldn't start. So I replaced the ecm, installed it and still nothing!!! Please help!!!
Cat 3406e 5ek70094 engine
Submitted: 5 years ago.Category: Medium and Heavy Trucks
Show More
Show Less
Ask Your Own Medium and Heavy Trucks Question
Answered in 2 hours by:
7/8/2017
Technician: Daniel Wilson,
 replied 5 years ago
Daniel Wilson
Category: Medium and Heavy Trucks
Satisfied Customers: 6,195
Experience: Owner at DJ Wilson
Verified

Hi, My name is***** will be glad to try to help. Check for an inline fuse between the battery box and ECM and for any damage or corrosion in the wiring. Let me know the engine model and serial number so I can get you the proper pinouts.

Ask Your Own Medium and Heavy Trucks Question
Customer reply replied 5 years ago
cat 3406e 5ek90074 as stated in my question. There is no inline fuse on this truck. There is an ecm fuse, behind the dash that runs to the ecm wire 455, fuse is good and I have power to the ecm.
Customer reply replied 5 years ago
I have power on pins 4 with key off and 6 with the key on and a ground on 5 at the ecm.
Was this answer helpful?

How JustAnswer works

step-image
Describe your issueThe assistant will guide you
step-image
Chat 1:1 with a technicianLicensed Experts are available 24/7
step-image
100% satisfaction guaranteeGet all the answers you need
Ask Daniel Wilson Your Own Question
Daniel Wilson
Daniel Wilson
Daniel Wilson
Category: Medium and Heavy Trucks
Satisfied Customers: 6,195
6,195 Satisfied Customers
Experience: Owner at DJ Wilson

Daniel Wilson is online now

Related Medium and Heavy Trucks Questions
I have a 1995 378 Peterbilt with 3406e and the Jake's stop
I have a 1995 378 Peterbilt with 3406e and the Jake's stop working. at first if I turned the switch off and on ,it would Actuate . but now something weird, if you press down on the brake pedal hard it… read more
SteveR
SteveR
Shop Manager
High school
6 satisfied customers
I have a catepillar 3406e Serial 2ws20176 i need a ecm pin
I have a catepillar 3406e Serial 2ws20176 i need a ecm pin out 70 pin My jake abd cruise don't work and i have et Showing service brake pedal on I check the brake switch and is good… read more
Nich1019
Nich1019
Diesel Technician
Vocational, Technical or Trade School
80 satisfied customers
I HAVE 2002 peterbilt 379 vin 1XP-5DB9X-0-2N573748, ITS A
I HAVE 2002 peterbilt 379 vin 1XP-5DB9X-0-2N573748 … read more
Nich1019
Nich1019
Diesel Technician
Vocational, Technical or Trade School
80 satisfied customers
I have a 2006 Peterbilt 387 with a MXS C 15 engine. My
I have a 2006 Peterbilt 387 with a MXS C 15 engine. My engine brake is not working and have been troubleshooting on my own with no luck. Cruise control works on idle. What can I do to start and rule o… read more
Nich1019
Nich1019
Diesel Technician
Vocational, Technical or Trade School
80 satisfied customers
Jake brake stopped working on our 2002 Peterbilt 379. It's
Jake brake stopped working on our 2002 Peterbilt 379 … read more
Nich1019
Nich1019
Diesel Technician
Vocational, Technical or Trade School
80 satisfied customers
Cruise will not work. 05 peterbilt 379 cat accert c 15.
Cruise will not work JA: What's the make/model/year of your truck? Engine type? Customer: 05 peterbilt 379 cat accert c 15 JA: Are you fixing your truck yourself? What have you tried so far? Customer:… read more
Nich1019
Nich1019
Diesel Technician
Vocational, Technical or Trade School
80 satisfied customers
I have a 2009 peterbilt 378 with a C15 cat in it and the
I have a 2009 peterbilt 378 with a C15 cat in it and the cruise control works but it will not resume any idea what that is … read more
Wayne
Wayne
Journeyman
Vocational, Technical or Trade Scho
5,115 satisfied customers
Hellow so i randomly got a flashing check engine light i
hellow so i randomly got a flashing check engine light i have a 2006 peterbilt 387 with 1,00,087 miles on it c15 eaton fuller 13 speed … read more
Nich1019
Nich1019
Diesel Technician
Vocational, Technical or Trade School
80 satisfied customers
I have a 379 Pete, the jake does not work. I have no power
I have a 379 Pete, the jake does not work. I have no power to the jake brake switch. Is this my problem?? … read more
Nich1019
Nich1019
Diesel Technician
Vocational, Technical or Trade School
80 satisfied customers
I did a engine swap on a 1994 Peterbilt 379 that had a model
I did a engine swap on a 1994 Peterbilt 379 that had a B model cat, I put a 3406e (6ts04777) I'm trying to hook up jakes and cruise but the wiring diagram doesn't explain what's 12volt power and groun… read more
catmastertech
catmastertech
Field service technician
Vocational, Technical or Trade Scho
1,325 satisfied customers
2003 peterbilt 378 vin 1CP-FDBOX-6-4D808339 cat C 15 MBN
2003 peterbilt 378 vin 1CP-FDBOX-6-4D808339 cat C 15 MBN jakes,cruise control quit working I'm looking for the inputs to J2 from cab switches test good & controlling ground I would like pin numbers at… read more
Nich1019
Nich1019
Diesel Technician
Vocational, Technical or Trade School
80 satisfied customers
I have a 1996 model 379 peterbilt with a cat 3406e in it.
I have a 1996 model 379 peterbilt with a cat 3406e in it. The cruise control has started not working intermittently. I thought it had to be the on/off switch so I changed it and it still does the same… read more
BrentR718
BrentR718
14 satisfied customers
I a cat c13 Avery and the Jake brake dose not work at all
I a cat c13 Avery and the Jake brake dose not work at all where do I start … read more
Cat Man
Cat Man
Cat Engine Expert
Vocational, Technical or Trade Scho
5,353 satisfied customers
We have a C15 Acert in a 2005 Peterbilt 378. The jake brake
We have a C15 Acert in a 2005 Peterbilt 378. The jake brake only works on low and before that it was working in every position but started cutting out. Now it is only giving us low and there is no pow… read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
6,195 satisfied customers
2004 Cat C15 in a Peterbilt 378, VIN. 1NPFXBEX34D830549.
2004 Cat C15 in a Peterbilt 378, VIN. 1NPFXBEX34D830549. Jake brake is not working. Checking for voltage at the power supply to the Jake on off switch with a power probe, key on engine off, it shows 1… read more
Cat Man
Cat Man
Cat Engine Expert
Vocational, Technical or Trade Scho
5,353 satisfied customers
It is a 95 Peterbilt with a 3406e. The Jake brake is not
It is a 95 Peterbilt with a 3406e. The Jake brake is not working on low stage. We have ruled out switch. Wondering if there was a relay that worked the Jake … read more
Cat Man
Cat Man
Cat Engine Expert
Vocational, Technical or Trade Scho
5,353 satisfied customers
I have a 2000 peterbilt 379exh with a cat 3406e 2ws truck
I have a 2000 peterbilt 379exh with a cat 3406e 2ws truck vin 508940. I need to know where the pressure switch for the cruise control is located.… read more
Cat Man
Cat Man
Cat Engine Expert
Vocational, Technical or Trade Scho
5,353 satisfied customers
I'm switching a 99 peterbilt from Detroit ddec3 to cat 3406e
I'm switching a 99 peterbilt from Detroit ddec3 to cat 3406e 40 pin. What do I need for the cab. I have the harness from the ecm to the firewall from a donor truck. … read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
6,195 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.

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

6,195 satisfied customers

Owner at DJ Wilson

Cat Man

Cat Man

Cat Engine Expert

5,353 satisfied customers

I am ASE Master Truck Certified.

Wayne

Wayne

Journeyman

5,115 satisfied customers

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

Jeremy

Jeremy

Certified Truck/Bus Technician

2,756 satisfied customers

ASE Med/HD Truck Technician, NATEF Diesel Engines and Electrical/Electronics Technician, Network Engineer specializing in CAN faults, Aftertertreatment, and vehicle communications

Curtis B.

Curtis B.

Technician

1,947 satisfied customers

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

cumminsdr

cumminsdr

Mechanic

1,886 satisfied customers

All types of Cummins applications

Chris (aka-Moose)

Chris (aka-Moose)

Technician

641 satisfied customers

24 years of experience diagnosing & repairing

< Previous | Next >

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