Medium and Heavy Trucks

Have truck repair questions? Ask an Expert

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

I turn the key on everything is normal then trun key more to…

Customer Question
I turn the key...

I turn the key on everything is normal then trun key more to start and nothing happens

Mechanic's Assistant: Does this happen when the vehicle is in park or neutral? Do you know if it has a "wheel lock" feature?

Its in neutral and should crank but nothing happens

Mechanic's Assistant: What's the make, model, and year of your car?

2012 cxu 613 Mack

Mechanic's Assistant: Is there anything else the Mechanic should know before I connect you? Rest assured that they'll be able to help you.

No its all pretty straight forward

Submitted: 1 year ago.Category: Medium and Heavy Trucks
Show More
Show Less
Ask Your Own Medium and Heavy Trucks Question
Answered in 54 minutes by:
7/31/2021
Technician: Edgar.T, Forman replied 1 year ago
Edgar.T
Edgar.T, Forman
Category: Medium and Heavy Trucks
Satisfied Customers: 46
Experience: Expert
Verified
What kind of transmission do you have?
Ask Your Own Medium and Heavy Trucks Question
Customer reply replied 1 year ago
AutomaticMack mDrive
Technician: Edgar.T, Forman replied 1 year ago
Mdrive correct? And you are getting neutral.
Ask Your Own Medium and Heavy Trucks Question
Technician: Edgar.T, Forman replied 1 year ago
Ok. Let’s try jumping the starter solenoid and see if it starts. This is a quick test to see if the starter is good.
Ask Your Own Medium and Heavy Trucks Question
Customer reply replied 1 year ago
It's good I did that this morning
Technician: Edgar.T, Forman replied 1 year ago
Hook up a multimeter to the small leads on the stater solenoid and crank the engine. It’s a 12v signal. You may need to check the wires one at a time to find out if your missing the ground or power.
Ask Your Own Medium and Heavy Trucks Question
Customer reply replied 1 year ago
One has 13 volts with key off and nothing changes when you try to start engineWhen it wouldn't start yesterday I changed the starter
Technician: Edgar.T, Forman replied 1 year ago
If you put your leads to the starter small wires and crank it what is your voltage?Reading must be taken with the key in the crank position
Ask Your Own Medium and Heavy Trucks Question
Customer reply replied 1 year ago
Didn't change 13v on one nothing on the otherThere is two other small posts where the engine wiring harness hooks to and they are Zero volts
Technician: Edgar.T, Forman replied 1 year ago
the smallest wires from the engine harness are your power and ground signal to crank. I believe there like 10mm nuts on the. The other two wire that are covered with a boot one is constant battery voltage. The ones we are checking are the engine harness side. Ok so you have 0v on the engine harness. Need to isolate if you are missing your ground signal or voltage. So you need to check the circuit one at a time. So for example To check the voltage side put one lead on the positive side and the other on a known good ground. And crank it.
Ask Your Own Medium and Heavy Trucks Question
Customer reply replied 1 year ago
that's what I did
Technician: Edgar.T, Forman replied 1 year ago
Ok so you have verified you are getting a good ground signal to the starter. But not the voltage. Let me pull up a schematic. Is the no crank after repairs were done or it just happened?
Ask Your Own Medium and Heavy Trucks Question
Customer reply replied 1 year ago
Truck was good when it was parked the next morning you can turn the key on everything comes on like normal but when you turn further to crank nothing happens
Technician: Edgar.T, Forman replied 1 year ago
Check relay RLY36This is the fuse panel by your feet on the driver side. The relay is directional it can be installed backwards and it will work.
Ask Your Own Medium and Heavy Trucks Question
Customer reply replied 1 year ago
Ok sorry I had a miscommunication with my man helping me there is 3v on both of those wires with the key on and when in start position the top one holds 3 and the bottom one goes to 0v ,,,, I'm going to try the relay
Customer reply replied 1 year ago
Tried the ignition relay it can only be installed one way but still doesn't work
Technician: Edgar.T, Forman replied 1 year ago
Do you have voltage to pin 30 on the relay? It is feed from fuse f7 from the fuse box in the center of the dash
Ask Your Own Medium and Heavy Trucks Question
Customer reply replied 1 year ago
How do I locate pin 30
Technician: Edgar.T, Forman replied 1 year ago
Look on the relay the pins are numbered. Then match the location to the fuse box. Be careful not to spread the pin on the fuse box as this will create another problem. Use an appropriate size test terminal.
Ask Your Own Medium and Heavy Trucks Question
Customer reply replied 1 year ago
Pin 30 has 0v
Technician: Edgar.T, Forman replied 1 year ago
It gets power from fuse f7 on the center dash panel
Ask Your Own Medium and Heavy Trucks Question
Customer reply replied 1 year ago
have power at f7
Technician: Edgar.T, Forman replied 1 year ago
Looks like you have an open from the fuse to the relay. If the fuse is good the relay should be getting voltage.
Ask Your Own Medium and Heavy Trucks Question
Customer reply replied 1 year ago
Ok open means a broke wire or bad connection between f7 and relay ?
Technician: Edgar.T, Forman replied 1 year ago
Correct
Ask Your Own Medium and Heavy Trucks Question
Customer reply replied 1 year ago
Thanks a lot
Customer reply replied 1 year ago
Ok thanks I will get back on it in the morning Thank you very muchCould you possibly send me any kind of a diagram of this
Technician: Edgar.T, Forman replied 1 year ago
I did. Is it not coming up for you?
Ask Your Own Medium and Heavy Trucks Question
Customer reply replied 1 year ago
I got it thanks
Customer reply replied 1 year ago
could you please send me some kinda picture showing where pin 66 on the pass thru 128 pin connector mine has no numbers on anything i can find
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
Mack cxu 613 won't crank. Check fuel filter warning came on,
Mack cxu 613 won't crank. Check fuel filter warning came on, so I had them changed. After starting the truck, it slowly died. After using primer and cranking the truck again, this time with foot on pe… read more
Mike Mcmillan
Mike Mcmillan
Triage Tech/Shop Foreman
Associates
593 satisfied customers
I forgot my cab light on overnight in my 2015 mack cxu. It
Hello. I forgot my cab light on overnight in my 2015 mack cxu. It drained my 7yr old batteries tremendously. I couldn't start the vehicle without getting a jump several times. I replaced the batteries… read more
Mike Mcmillan
Mike Mcmillan
Triage Tech/Shop Foreman
Associates
593 satisfied customers
WORKING ON A 2013 MACK CXU 613. THIS TRUCK HAS THREE
WORKING ON A 2013 MACK CXU 613. THIS TRUCK HAS THREE CIGARETTE LIGHTER LOCATIONS ON THE INSTRUMENT PANEL. WHICH FUSE SUPPLIES THE POWER ? … read more
Mike Mcmillan
Mike Mcmillan
Triage Tech/Shop Foreman
Associates
593 satisfied customers
Speedometer quits working and the truck loses power. 2013
speedometer quits working and the truck loses power. 2013 mack mp8 … read more
Mike Mcmillan
Mike Mcmillan
Triage Tech/Shop Foreman
Associates
593 satisfied customers
2014 mack with a cxu 613 mp7 and im having issues with this
2014 mack with a cxu 613 mp7 and im having issues with this engine having high crankcase pressure and is pouring it out of the pcv assembly, down to the vent tube. we have done an overhaul on it and b… read more
Mike Mcmillan
Mike Mcmillan
Triage Tech/Shop Foreman
Associates
593 satisfied customers
Its saying this but its got to be simple its shifting all
its saying this but its got to be simple its shifting all gears not missing a beat shifting its just. crazy one min it drives good. Like nothings wrong then its goes to stoping at a complete stop like… read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
6,195 satisfied customers
My 2012 mack cxutransmission going in 1 an 2 an going
My 2012 mack cxu*****transmission going in 1 an 2 an going straight to 12 gear its saying sum bout lock up clutch pressure indicator an it saying transmission shift console primary … read more
Mike Mcmillan
Mike Mcmillan
Triage Tech/Shop Foreman
Associates
593 satisfied customers
2014 mack cxu 613 mp7 engine code p0016 keeps coming back.
2014 mack cxu 613 mp7 engine code p0016 keeps coming back. we have replaced the harness and engine rebuild as well, im asking if you could help me out as they dont have alot of info on this code. than… read more
Mike Mcmillan
Mike Mcmillan
Triage Tech/Shop Foreman
Associates
593 satisfied customers
My Mack cxu 613 is saying check fuel filter. It is also
My Mack cxu 613 is saying check fuel filter. It is also sputtering and occasionally the speed decreases … read more
Mike Mcmillan
Mike Mcmillan
Triage Tech/Shop Foreman
Associates
593 satisfied customers
Can you tell me what is this codes o my 2011 Mack prelude
Can you tell me what is this codes o my 2011 Mack prelude cxu613 codes MID 144 , psid 34 , fmi 4 … read more
Wayne
Wayne
Journeyman
Vocational, Technical or Trade Scho
5,115 satisfied customers
The ignition is not generating power. Make is Mack, model
I checked my batteries and alternator and it seems fine. I guess it's a wiring issue… read more
Mike Mcmillan
Mike Mcmillan
Triage Tech/Shop Foreman
Associates
593 satisfied customers
13 Penn Mack cxu will not trun over new starter switch get
13 Penn Mack cxu will not trun over new starter switch get power to starter alt but switch reading 11.5 … read more
Mike Mcmillan
Mike Mcmillan
Triage Tech/Shop Foreman
Associates
593 satisfied customers
Message on dash; guard dog check fuel filter, no codes or
Message on dash; guard dog check fuel filter , no codes or anything ?? … read more
Mike Mcmillan
Mike Mcmillan
Triage Tech/Shop Foreman
Associates
593 satisfied customers
It has started leaking fuel back out of the head overnight.
It has started leaking fuel back out of the head overnight. It is losing its prime.I was going to replace the check valve on the return line but do not know where it is located. … read more
Mike Mcmillan
Mike Mcmillan
Triage Tech/Shop Foreman
Associates
593 satisfied customers
2014 Mack CXU 613 is not getting fuel after new filter
2014 Mack CXU 613 is not getting fuel after new filter housing and fuel pump. Is there a complete fuel system diagram?… read more
Mike Mcmillan
Mike Mcmillan
Triage Tech/Shop Foreman
Associates
593 satisfied customers
Have a 2012 Mack with a mp7 had a code for fan clutch had it
Have a 2012 Mack with a mp7 had a code for fan clutch had it in a shop they verified I replaced the fan clutch no codes now but still have no manifold pressure are boost pressure … read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
6,195 satisfied customers
2014 mack cxu 613 mp8 with m drive will not crank has acc no
2014 mack cxu 613 mp8 with m drive will not crank has acc no data on information screen in dash and gear selector has ** instead of n1 truck has lots of codes active when not cranking,tow truck in it … read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
6,195 satisfied customers
Location of brake light switch 2012 mack cxu 613 with
location of brake light switch 2012 mack cxu 613 with automated transmission truck will not shift out of neutral when pressing brake pedal and has no brake lights on tractor message across screen says… read more
Jeremy
Jeremy
Certified Truck/Bus Technician
Associate Degree
2,756 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