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Jeremy, Certified Truck/Bus Technician
Category: Medium and Heavy Trucks
Satisfied Customers: 3320
Experience:  ASE Med/HD Truck Technician, NATEF Diesel Engines and Electrical/Electronics Technician, EPA 608/609 HVAC Certified, Steering/Suspension and ABS/Brakes Technician
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I have a 2007 mack granite with a mp7 motor, abs light on no

Customer Question

i have a 2007 mack granite with a mp7 motor, abs light on no start
JA: What's the make/model/year of your truck? Engine type?
Customer: 2007 mack granite with mp7
JA: Are you fixing your truck yourself? What have you tried so far?
Customer: replaced cam sensor, oil pressure sensor, checked ecm connections
JA: Anything else you want the truck mechanic to know before I connect you?
Customer: no
Submitted: 10 months ago.
Category: Medium and Heavy Trucks
Expert:  Jeremy replied 10 months ago.

My name is ***** ***** I will assist you with your question today.

I'm an independent contractor and I don't get paid until a rating has been made.

We can go back and forth as needed to help resolve the issue you are having. Follow ups are free after ratings, so rate in confidence!

Why was the cam sensor changed?

Do you have a scan tool to read codes on the engine?

ABS will not make the truck not start. Do you get the shut down light or the electrical bolt? Is the regen light blue or another color or flashing?


You want a 5 star service and I want to provide a 5 star service. Please consider that I don't know your skill level as well as I can't see, touch, smell, hear the vehicle/machine in question. Please provide as much detail as possible and I will provide as much back.

Once an answer is provided, you should see a rating screen. Please rate my personal service to you. The ratings are my personal feedback, they are not the site feedback.

Thank you for allowing me to assist you through Just Answer!


Customer: replied 10 months ago.
Can sensor was changed because my mechanic suggested it. He has gone over it 9 hours to no avail. Yes the lightning bolt is lit. The oil pressure is not registering on dash, neither are the hours. We are getting oil pressure though, we put a mechanical gauge in place of the oil pressure sensor and it was reading 50 psi with just Turing the truck over. The truck will fire off ether when spraying, but quits when you stop spraying. My mechanics scan tool is unreliable for the Mack trucks.
Customer: replied 10 months ago.
Also cleaned all battery connections today.
Expert:  Jeremy replied 10 months ago.

If you are not getting the hours display, you are not getting communication between the VECU and the ECU on the truck. This can be due to no power to the ECM or anotherr issue in the harness.

At this point, I would highly suggest getting someone with the PTT program to look at the engine and see why there is no communication or you are seriously just throwing money away.

The lack of the hours on the display screams out to me there is no communication between the modules and the question is why. Is the EVECU not powering up and sending the signal that hte ECM needs to run for the ignition is on or is the ECM not powering properly? The lightning bolt indicates there is a fault, but with the truck not running, you should have the shut down light on indicating the ECM is powered. Without that, you have no indication that the ECM is powering properly.

i know the frustration. I've been in that boat working on a fleet of MRU garbage trucks with the same engine and had fought for hours and hours without PTT and finally broke down to get it. It saves a ton of time on these.

Customer: replied 10 months ago.
I've heard some of these have a separate power wire to power the ecm?
Expert:  Jeremy replied 10 months ago.

Yes, some of them do. The MRUs use a power wire to the battery wit ha 10 AMP fuse. The Granites which is usually the Ch or the CX bodies don't always use them. It wouldn't hurt to look.

PINS 57 and 60 are what feed the EMS aka ECM. CLICK HERE for the power diagram sheet for the ECM.

Customer: replied 10 months ago.
where can I purchase one of those ptt scanners
Expert:  Jeremy replied 10 months ago.

Volvo or look online for them. There are several places that have them with the software and cloned scanners. It just depends on how much you want to spend and if you want authentic scanners or clones.

Alibaba has clones.

Volvo/Mack has them CLICK HERE and they are pricey. A lot of single truck operators (non-mechanics) get the cracks and then order the Nexiq adapters for them. Just browse for Volvo PTT Scanner or Volvoe PTT cracks and you can locate them.

I got mine from my dealer which give me programming access. If you don;t need programming, then you really don't need to get from them.

Customer: replied 10 months ago.
I can test those pins in the harness to determine if it has power?
Customer: replied 10 months ago.
Also if I am testing for power in the harness, how do determine which one is 57/60
Expert:  Jeremy replied 10 months ago.

CLICK HERE for the pins. It is setup just as you look at the EMS. Top is the to plug, bottom is the bottom plug.

My power is fluctuating as they restore power from the hurricane so my responses are slow.

Customer: replied 10 months ago.
There is two plugs on the ecm correct? Which one is it.
Customer: replied 10 months ago.
I confirmed I have power to ecm via 57/60 pins in harness. What next.
Customer: replied 10 months ago.
Can you confirm the part number for the ecm needed and what years with cross over? I have attached the vin.
Customer: replied 10 months ago.
Here is the engine label

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