Medium and Heavy Trucks

Have truck repair questions? Ask an Expert

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

This answer was rated:

I have a 2008 Mack MP7 engine. I have a problem with the…

I have a 2008 Mack...
I have a 2008 Mack MP7 engine. I have a problem with the compression brake solenoid. Scan shows low voltage when commanded by ECM to go high. Looking for wiring circuit info or possible causes.
Show More
Show Less
Ask Your Own Medium and Heavy Trucks Question
Answered in 6 hours by:
10/26/2018
Technician: Mike Mcmillan, Shop Foreman/Triage Tech replied 4 years ago
Mike Mcmillan
Mike Mcmillan, Shop Foreman/Triage Tech
Category: Medium and Heavy Trucks
Satisfied Customers: 6,790
Experience: Volvo/Mack Master Tech, Certified with Cummins, Eaton, GM, Hino, Detroit Diesel
Verified

Hello, My name is***** am a Mack and Volvo master tech, Please allow me to assist you with your issue. Please allow me a min to look this schematic up and I will post it to this case. Thanks

Ask Your Own Medium and Heavy Trucks Question
Technician: Mike Mcmillan, Shop Foreman/Triage Tech replied 4 years ago

Please see the attachment for the schematic requested. Has the main power sure been checked? Usually what we find with these is one of the other main components are shorting out since they have a common with 2 other valves. Please let me know if you have any other questions. Thanks.

Mike Mcmillan
Mike Mcmillan, Shop Foreman/Triage Tech
Category: Medium and Heavy Trucks
Satisfied Customers: 6,790
Experience: Volvo/Mack Master Tech, Certified with Cummins, Eaton, GM, Hino, Detroit Diesel
Verified
Mike Mcmillan and 87 other Medium and Heavy Trucks Specialists are ready to help you
Ask your own question now
Customer reply replied 4 years ago
This is the first MP7 for me. I looked at the schematic it says the fuse for the comp. brake solenoid is fuse #2 in the engine compartment , I have not found any fuses in the engine compartment. I do have a fuse panel on top of the dash and one at the kick panel by the drivers door, but it does not have a label . The model of this truck CTP713. I have not checked the power yet . I will do that now.
Technician: Mike Mcmillan, Shop Foreman/Triage Tech replied 4 years ago
Phone call session started
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 Mike Mcmillan Your Own Question
Mike Mcmillan
Mike Mcmillan
Mike Mcmillan, Shop Foreman/Triage Tech
Category: Medium and Heavy Trucks
Satisfied Customers: 6,790
6,790 Satisfied Customers
Experience: Volvo/Mack Master Tech, Certified with Cummins, Eaton, GM, Hino, Detroit Diesel

Mike Mcmillan is online now

Related Medium and Heavy Trucks Questions
Truck is Mack *****************, model ch613. Fan is staying
Truck is Mack *****************, model ch613. Fan is staying engaged all the time. No active codes. Fan is the electric model. Need troubleshooting to verify fan is bad.… read more
Matthew Hino
Matthew Hino
Hino Master Elite Technician
Vocational, Technical or Trade School
1997 Detroit Series 60, getting a code “auxiliary output
1997 Detroit Series 60 , getting a code “auxiliary output device #3” voltage above normal or shorted high, Number SS1,mode 3 what to check to trace issue??… read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
6,062 satisfied customers
I need wire diagram for mack truck 2018 do u have that
i need wire diagram for mack truck 2018 do u have that abilty and can u send me a link to sigh up … read more
Mike Mcmillan
Mike Mcmillan
Shop Foreman/Triage Tech
Associates
6,790 satisfied customers
Need in depth help on 2008 mp7. Truck will not start has
Truck will not start has lost rpm and oil pressure. Ecm has good power … read more
Mike D
Mike D
Mechanic Shop foreman
diesel technology
2 satisfied customers
Mack mp7 i need ecm pin out. 2007 mack granite with mp7
mack mp7 i need ecm pin out JA: What's the make, model, and year of your car? Customer: 2007 mack granite with mp7 motor JA: Anything else you want the Mechanic to know before I connect you? Customer:… read more
Mike Mcmillan
Mike Mcmillan
Shop Foreman/Triage Tech
Associates
6,790 satisfied customers
2017 mack mp7 code p113712 oil thermostat short to
2017 mack mp7 code p113712 oil thermostat short to battery..... What is the best way to go about diagnosing this code?… read more
RichardH416
RichardH416
Resident Tech
Associates
75 satisfied customers
I have a 2008 CTP713 Mack with an MP7 engine, When I hook up
I have a 2008 CTP713 Mack with an MP7 engine, When I hook up to the truck I get an abnormal update rate code. The engine will not start, the battery voltage is 11.5 with starter engaged, I have checke… read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
6,062 satisfied customers
Have a tricky problem with low-high compression brakes on a
Have a tricky problem with low-high compression brakes on a C-15. Original concern was jakes not hitting on high. pulled valve covers and determined low-high jakes only actuated on low. scanner showed… read more
catmastertech
catmastertech
Field service technician
Vocational, Technical or Trade Scho
1,325 satisfied customers
2015 Mack LEU MP7 Codes DTC P25AA DTC P0480 DTC P1137 Low
2015 Mack LEU MP7 Codes DTC P25AA DTC P0480 DTC P1137Low power, when rev up goes to 1800RPM and then fluctuates down to 15-1600RPMHow do I start troubleshooting?… read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
6,062 satisfied customers
2010 mack MP7 450 now in regeneration zone 4 with soot level
2010 mack MP7 450 now in regeneration zone 4 with soot level at 140 % when I start a force regeneration my after treatment fuel injection pressure starts at 65psi but quickly drops to 3psi and my exha… read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
6,062 satisfied customers
I am having problem with my machine, stating that there is
I am having problem with my machine, stating that there is low voltage or open circuit in the injector … read more
cumminsdr
cumminsdr
Mechanic
High School or GED
1,886 satisfied customers
I have a service engine code of 64704. It is a model isl
I have a service engine code of 64704 JA: What is the complete model and serial number of your machine? Customer: It is a model isl serial number 46604049 JA: Are you fixing this yourself? What have y… read more
cumminsdr
cumminsdr
Mechanic
High School or GED
1,886 satisfied customers
Was driving and all over a sudden the truck has no throttle
Was driving and all over a sudden the truck has no throttle response and check engine on … read more
Edward Haniewski
Edward Haniewski
General Studies/Automotive
1 satisfied customers
It is a freightliner Century 2007. Detroit Diesel series 60
It is a freightliner Century 2007. Detroit Diesel series 60 and Meritor gearbox with 10 speed. Will not shift into high range. Not gear shift switch or air solenoids. Damaged wiring which has been rep… read more
Expert
Expert
5 satisfied customers
I have 2008 mack gu 713 dump truck with mp7, 85000 miles &
I have 2008 mack gu 713 dump truck with mp7, 85000 miles & each time it regens loose about half gallon of oil out of blow by tube. … read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
6,062 satisfied customers
I have a 2005 Mack LE no throttle drivers side throttle
I have a 2005 Mack LE no throttle drivers side throttle works on stand up RH side EML light and ABS light on Cruise switch doesn't work to advance idle … read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
6,062 satisfied customers
2007 MP7 runs good in lower ear but looses power in higher
2007 MP7 runs good in lower ear but looses power in higher gear (spped ) no manifold pressure … read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
6,062 satisfied customers
have a mack mru 2008 model with a mp7. only running on cylinders
have a mack mru 2008 model with a mp7. only running on cylinders 1,2,3. has active codes sid4 fmi5, sid5 fmi5, sid6 fmi5. have continuity from pin61 to 52,44, and 36. also have it from 60 to 56,48 and… read more
JCTech
JCTech
Technical Specialist
Vocational, Technical or Trade Scho
352 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

6,062 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