Medium and Heavy Trucks

Have truck repair questions? Ask an Expert

Ask an Expert,
Get an Answer ASAP!

Hellev my name is eddie masson i have a frightliner in my…

Customer Question
hellev my name is *****...
hellev my name is ***** ***** i have a frightliner in my shop with a ism cummins engine won,t start it will crank over starts with sarting fluid but won.tstay running.i change timming sensor,bromatic sensor,oil sensor,ecm,fuel pump,have power to the ecm,ran a hose from from pump to 5gl of fuel,and nothing any the only code it give me is 0434
Submitted: 2 years ago.Category: Medium and Heavy Trucks
Show More
Show Less
Ask Your Own Medium and Heavy Trucks Question
Answered in 4 hours by:
1/24/2016
Technician: Jeremy, Certified Truck/Bus Technician replied 2 years ago
Jeremy
Jeremy, Certified Truck/Bus Technician
Category: Medium and Heavy Trucks
Satisfied Customers: 3,856
Experience: ASE Med/HD Truck Technician, NATEF Diesel Engines and Electrical/Electronics Technician, EPA 608/609 HVAC Certified, Steering/Suspension and ABS/Brakes Technician
Verified

My name is ***** ***** I will assist you.

Please don't forget to rate above. I'm an independent contractor that is oaid oer question. No rsting means site gets it all and zi get nothing. Same as negative rating.

CODE REASON

Fault Code: 434
PID: S251
SPN: 627
FMI: 2
LAMP: Yellow
SRT:

Supply voltage fell below (+) 6.2 VDC for a fraction of a second, or the electronic control module (ECM) was not allowed to power down correctly (retain battery voltage for 30 seconds after key-off).

The ECM receives constant voltage from the batteries through the unswitched battery wires that are connected directly to the positive (+) battery post. There are three in-line 7.5-amp fuses and one 20-amp fuse in the unswitched battery wires to protect the engine harness from overheating. The ECM receives switched battery input through the vehicle keyswitch wire, when the vehicle keyswitch is turned on

Make sure that ECM unswitched power is coming from the batteries and not the starter. Check for low voltage during cranking. Low voltage during cranking can cause the ECM power supply to drop below specifications and log Fault Code 434.

Corrupted voltage (short interruptions or spikes that may only be seen with an oscilloscope) on keyswitch line can cause this fault. If the voltage at pin 5 of engine connector is measured as negative with oscilloscope at key-off, Fault Code 434 can be logged.

A failure with the ECM can also cause this. Try a test ECM for the same vehiclenof you have one.

You can also shake the harness while you the vehicle is running to see if the vehicle shuts down.

Ask Your Own Medium and Heavy Trucks Question
Technician: Jeremy, Certified Truck/Bus Technician replied 2 years ago

I see you viewed this and this is still showing as a open question due to no positive (3 stars or more) rating.

Did you still need assistance with this?

Ask Your Own Medium and Heavy Trucks Question
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 Jeremy Your Own Question
Jeremy
Jeremy
Jeremy, Certified Truck/Bus Technician
Category: Medium and Heavy Trucks
Satisfied Customers: 3,856
3,856 Satisfied Customers
Experience: ASE Med/HD Truck Technician, NATEF Diesel Engines and Electrical/Electronics Technician, EPA 608/609 HVAC Certified, Steering/Suspension and ABS/Brakes Technician

Jeremy 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

2,803 satisfied customers

Owner at DJ Wilson

Cat Man

Cat Man

Cat Engine Expert

4,530 satisfied customers

I am ASE Master Truck Certified.

Wayne

Wayne

Journeyman

2,892 satisfied customers

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

Jeremy

Jeremy

Certified Truck/Bus Technician

3,856 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

1,351 satisfied customers

All types of Cummins applications

Curtis B.

Curtis B.

Technician

991 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 have a 2008 cummins ISM 350 that will crank but will not
I have a 2008 cummins ISM 350 that will crank but will not start. Cranking fuel pressure is 18 psi with new cummins reman pump. I have no CEL and no codes. It will start with starting fluid and runs f… read more
Andy3221
Andy3221
truck /coach technician
Vocational, Technical or Trade Scho
222 satisfied customers
2002 Freightliner Vin K43874 Need wiring schematic from
2002 Freightliner Vin K43874 Need wiring schematic from ignition to fuel shut off solenoid. With key on power to fuel shut off solenoid pulsing 4 volts.… read more
cumminsdr
cumminsdr
Mechanic
High School or GED
1,351 satisfied customers
Ism cummins will not start check elec light on wire going to
ism cummins will not start check elec light on wire going to shutoffsolenoid not energized … read more
cumminsdr
cumminsdr
Mechanic
High School or GED
1,351 satisfied customers
I have a 2005 cummins ism, just overhauled engine, went to
I have a 2005 cummins ism, just overhauled engine, went to start engine after overhaul, will not start, have over 25 psi fuel pressure at crank, communicating with ecm, engine speed good, no codes, I … read more
cumminsdr
cumminsdr
Mechanic
High School or GED
1,351 satisfied customers
M11 celect 1993 freightliner crank no start. Fuel going into
M11 celect 1993 freightliner crank no start. Fuel going into head, 30 psi, hooked up hoses into bucket, same result, put noid light on injector harness and got signal, both fuses and grounds going int… read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
2,803 satisfied customers
We have a cummins n14 here and the unit runs great but does
we have a cummins n14 here and the unit runs great but does not start unless hit with starting fluid and starts and runs doesnt sound like it has air in the system just fires right up customer has put… read more
Dorian Conley
Dorian Conley
Heavy Duty Diesel Engine Technician
Vocational, Technical or Trade School
My Cummins 400 ism starts and runs fine for 30 to50 seconds,
My Cummins 400 ism starts and runs fine for 30 to50 seconds, then starts crapping out and dies. I replaced the fuel transfer pump, fuel filter, fuel, etc, checked for suction air leaks etc.Now what? … read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
2,803 satisfied customers
2008 MS FRIGHTLINER MBE 900 CRANKS DONT START-MANUALY PRIME
2008 MS FRIGHTLINER MBE 900 CRANKS DONT START-MANUALY PRIME FUEL RUNS ABOUT 10 MIN AT IDLE ---THEN STALLS-LOOK FOR VAC LEAKS AND RELPACED FUEL PUMP --CODE 248 FAULT 09… read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
2,803 satisfied customers
I have a 1999 International with a Detroit 60 series. Can
I have a 1999 International with a Detroit 60 series. Can the ECM cause a no fuel issue? We pulled the fuel pump off and there was liquid (oil like) inside when we pulled it away from the compressor. … read more
spankyjr1
spankyjr1
Retired
Vocational, Technical or Trade Scho
19 satisfied customers
My brand new genset with a cummins QSX15 ran well the first
My brand new genset with a cummins QSX15 ran well the first start. Next day it wouldn't start.cummins South Africa technicians baffled. HELP… read more
Andy3221
Andy3221
truck /coach technician
Vocational, Technical or Trade Scho
222 satisfied customers
2006 international 7600 w cummins engine, stalled got towed
2006 international 7600 w cummins engine, stalled got towed in will only start with starting fluid. I need to know how the fuel gets pumped from tank to injection pump. there is a fuel cut off solenoi… read more
spankyjr1
spankyjr1
Retired
Vocational, Technical or Trade Scho
19 satisfied customers
I have a ford 9000 that wont start has a n14 cummins can not
i have a ford 9000 that wont start has a n14 cummins can not find a diagnostic connector under dash or on the engine… read more
spankyjr1
spankyjr1
Retired
Vocational, Technical or Trade Scho
19 satisfied customers
2000 sterling carhauler ism cummins and auto shift....will
2000 sterling carhauler ism cummins and auto shift....will not run after I installed a new starter… read more
Jeremy
Jeremy
Certified Truck/Bus Technician
Associate Degree
3,856 satisfied customers
Have a cummins ISM in a freightliner. Very hard starting and
Have a cummins ISM in a freightliner. Very hard starting and rough idle. Have active codes for engine speed sensor and vehicle speed sensor. Sets an engine position sensor code during cranking, but no… read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
2,803 satisfied customers
What causes the external fuel command code to come on continuously
What causes the external fuel command code to come on continuously on a cummins ism. engine… read more
Andy3221
Andy3221
truck /coach technician
Vocational, Technical or Trade Scho
222 satisfied customers
Hi, Im having a problem with a Cummins ISC with the CAPS fuel
Hi, I'm having a problem with a Cummins ISC with the CAPS fuel pump. It will not start when it's hot. 150 to 180 degrees engine temp. The only way it will start is using a little starting fluid. It st… read more
FIX-IT
FIX-IT
Comercial transport technician
Vocational, Technical or Trade Scho
784 satisfied customers
hello I have a 2006 7600 international with ism cummins engine
hello I have a 2006 7600 international with ism cummins engine ok the engine was bad so we went to the yonk yard and we put another engine 2005 ism but wont start when is cranking has 3o-40 psi of fue… read more
cumminsdr
cumminsdr
Mechanic
High School or GED
1,351 satisfied customers
2007 International 8600 fuel transfer pump dose not work.
2007 International 8600 fuel transfer pump dose not work. Transfer pump relay and both sensors are new. Still no fuel transfer. Has a Cummins ISM. I read in my repair manual their is a system controll… read more
sevn103
sevn103
263 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