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Daniel Wilson
Daniel Wilson,
Category: Medium and Heavy Trucks
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Please help. NO CLICK NO CRANK. I have 2007 Volvo VNL with

Customer Question

Please help. NO CLICK NO CRANK. I have 2007 Volvo VNL with ISX CM870 Cummins.
Submitted: 6 months ago.
Category: Medium and Heavy Trucks
Customer: replied 6 months ago.
Starter is good. fuses are good.
Expert:  William Herren replied 6 months ago.
Hello, I would like to help you with this issue. Have you checked voltage to the starter solenoid?
Customer: replied 6 months ago.
A few weeks ago I would attempt to start my truck but nothing happens (no click no crank). I would try again a few seconds later and it fires right up. That would happen once every 4 to 5 days or so. In the last ten days it started happening 2 or 3 times a day until 2 days ago it would not start at all. I tried and tried......nothing. no click no crank. I was at a truck stop in Oklahoma when this happened. A fellow driver suggested I use a screw driver to jump the relay/solenoid on the fire wall. It worked and headed home to Dallas, TX. I bought a new relay and installed it on the fire wall. Still nothing! I got my tester light and hooked it up to the negative on the battery. I had my son hold the key in the start position and when using the tester, I noticed that the two small posts that are used to energize the relay/solenoid on the fire wall are HOT as in positive. The problem is that both posts are positive instead of one being positive and one being negative to make the solenoid work the way it should.
Expert:  William Herren replied 6 months ago.
A relay will have at least to hot post on them. One hot post is connected to the coil which controls the relay. By exciting that pole (we will call 85) and giving a ground to the other side of the coil (we will call 86) you allow power to flow through two other poles (we will call 87 and 30). This is how a common relay works. The relay on the firewall works in the same manner but at higher amperage. So when you turn the key on the steering column it allows a small wire to excite the solenoid on the firewall which uses a larger gage wire to excite the starter solenoid. I would check to see if there is voltage at the starter solenoid as the next step.
Customer: replied 6 months ago.
You are correct and I agree with everything you mentioned. The problem I am having is that 85 and 86 are hot when attempting to start the truck. So basically it's not being excited to connect 87 with 30. I would have to connect 87 and 30 using a screw driver. Like you said only one should be hot and the other should be ground. I even connected my tester to the positive on the battery post and verified that a ground is NOT present at 85 or 86 when attempting to start the truck.
Expert:  William Herren replied 6 months ago.
It sounds like a wire is connected to the wrong post. Can you disconnect the relay, and determine which wire is excited when the key is turned to start position? If so, that is your starter wire. That wire needs to excite the coil while the other hot wire, which should have battery power all the time provides power to the starter.
Customer: replied 6 months ago.
I add this picture to make sure we are on the same page. Please keep in mind that I had this truck for 3 years with no issue. so when you say a wire is connected to the wrong post, I really doubt it. I will be able to disconnect it tomorrow and see which one is excited when attempting to start the truck.
Expert:  William Herren replied 6 months ago.
I agree you have it labeled correctly. You have to understand that I have to go by what information you have given me. I work with lots of people each day so I have to be direct and clear as I don't know each persons skill level.
Expert:  William Herren replied 6 months ago.
Also, check to ensure you have a good ground.
Customer: replied 6 months ago.
Good ground at where?
Expert:  William Herren replied 6 months ago.
85 should be hot when key is turned to start position. 86 should be ground. 87 should be battery voltage all the time and 30 should run to your starter solenoid.
Customer: replied 6 months ago.
You are correct, but when I tried to apply a ground to 85 or 86 while the wires were connected, it started sparking and I didn't want to push my luck. I took the wires off and tried applying a positive to 86 and a ground to 85 straight from the battery and it was working and clicking. So basically my problem is in the the 2 little wires that connect to 85 and 86.
Expert:  William Herren replied 6 months ago.
One should be your wire from the ignition that supplies power to the relay when the key is turned on and the other should be a ground.
Customer: replied 6 months ago.
correct but the problem is that both 85 and 86 are hot. If I can fix that, then my problem is fixed.
Expert:  William Herren replied 6 months ago.
Yes, you have them hooked wrong. They can't both be hot. There has to be a ground.
Customer: replied 6 months ago.
I understand that part and I didn't hook any thing up. That is the problem I am having. If one was hot and the other is ground I would not be on the here trying to figure it out. I need to know what is causing my truck to make both wires hot. Please keep in mind that this is a Volvo, not your basic KW or Peterbilt which are more basic.
Expert:  William Herren replied 6 months ago.
It is possible you have to hot wires that go to 85, but you have to have a ground that goes to 86. Sometimes when there is an automated or automatic transmission they use that wire to wake the trans control unit up prior to start. Isolate which wire is hot when key is turned on and connect it to 85. Identify the ground and connect it to 86. Determine your constant battery voltage (generally larger wire) and connect it to 30, connect wire to your starter solenoid to 87.
Expert:  William Herren replied 6 months ago.
I you can please try that and tell me if the truck will crank. If so, we will determine what the other wire is powering.
Customer: replied 6 months ago.
I have a 13 speed. The larger wires are already connected to 30 and 87 (that's how I start the truck using a screw driver). Identifying the ground is the challenge. I will have to check them tomorrow during the day. I will take both wires off 85 and 86. I will attempt to start the truck and see at least which wire is hot. I doubt I will find a ground, but at least I will find the hot.
Expert:  William Herren replied 6 months ago.
Ok, check all around. It is possible the connector broke, there has to be a ground for it.
Customer: replied 6 months ago.
good morning. I am heading out right now to check out the wires. Give me a few minutes.
Customer: replied 6 months ago.
As stated before, both wires at 85 and 86 are coming in hot when attempting to start the truck. I also tested all the ignition relay to make sure they are functioning and all fuses are good. That's why it took so long. Do you have a schematic that we can go back to and trace both wires to?
Expert:  William Herren replied 6 months ago.
Yes, can you give me your engine serial number.
Expert:  William Herren replied 6 months ago.
I need the engine serial number to check wiring. It is located on the left side of engine.
Customer: replied 6 months ago.
ESN 79154119
Expert:  William Herren replied 6 months ago.
So with the key in start position both of the small wires are hot. Is one of them hot all the time?
Customer: replied 6 months ago.
That is correct. Both are hot when the key is in the start position ( can send you 2 pictures if you like). No non of them are hot all the time.
Expert:  William Herren replied 6 months ago.
Thank you!
Expert:  William Herren replied 6 months ago.
Please send pics
Customer: replied 6 months ago.
Here are the pictures. As you can see both are hot when attempting to start the truck.
Expert:  William Herren replied 6 months ago.
It only shows one hot wire to the magnetic switch from the ignition. Try this, make a temporary ground from 86 to the frame or engine block. Connect, both of the ignition wires to 85. Start engine and make sure no fuses are blown.
Customer: replied 6 months ago.
It works the way it should. But again, the million dollar question is, what is causing both wires to come in hot when a few days ago it was fine?
Expert:  William Herren replied 6 months ago.
Do both wires look like they came from factory?
Customer: replied 6 months ago.
yes sir and they are labeled with numbers just like RV wires.
Expert:  William Herren replied 6 months ago.
What are the numbers on the wires?
Customer: replied 6 months ago.
The one with the yellow connector is 284-A & and the regular connector is 990-A
Customer: replied 6 months ago.
I think I figured it out.
Expert:  William Herren replied 6 months ago.
Ok, I would appreciate a 5 star rating. If more information is needed please let me know.
Customer: replied 6 months ago.
We are not done yet. I was able to get this from the internet. Please look at it and tell me what you think.
Customer: replied 6 months ago.
990-A is for the over crank protection (OCP). I did crank it a lot 2 months ago when I ran out of fuel trying to prime it. and shortly this started happening. It makes sense. The question is where is the over crank protection (OCP) located and how can I change it?
Expert:  William Herren replied 6 months ago.
The ocp should be located on the rear of the starter. There is a connector with two wires
Customer: replied 6 months ago.
let me go check it out.
Customer: replied 6 months ago.
I got a picture of the starter. I don't see it. Unless it's somewhere else. Does the schematic I sent you make any sense as to why both are positive and to how the OCR is a cause?
Expert:  William Herren replied 6 months ago.
The ocr would be below the ground stud on the starter. That little isolator with a stud and nut is where it would be.
Expert:  William Herren replied 6 months ago.
The only other thing I can think of is it goes to a clutch safety switch and is grounded through that. Will your truck start without the clutch pedal down?
Customer: replied 6 months ago.
I don't have to press the clutch to start my truck. Nothing was connected to that stud when I took off the starter. There are no broken wires or even broken tabs on that stud when I took it off. I even took the nut off now just to check and nothing.
Expert:  William Herren replied 6 months ago.
Have you ever had to press the clutch in to start your truck?
Customer: replied 6 months ago.
never.
Expert:  William Herren replied 6 months ago.
Have you checked your clutch switch to see how it was bypassed?
Customer: replied 6 months ago.
no. I don't think it is the clutch switch (if there is one). I will take out the panel and check.
Expert:  William Herren replied 6 months ago.
That is what your wire 284-A goes too.
Customer: replied 6 months ago.
Just tested the clutch switch and it has power (hot) and functions properly. I think its function is to disengage the cruise control which I have used before. The 284-A is functioning properly and is hot as intended when attempting to start the truck. The problem is in the 990-A which should be ground according to the schematic I sent you. Please correct me if I am wrong.
Expert:  William Herren replied 6 months ago.
It should be ground, the schematic shows two versions. One version which it get a ground from an over crank protection. The other instance shows it just looping down to the ground stud on the starter.
Customer: replied 6 months ago.
I am sorry. You lost me. are you saying 284-A should be ground or 990-A?
Expert:  William Herren replied 6 months ago.
990-A should be ground
Customer: replied 6 months ago.
On the schematic it shows 990-A to be ground on the OCP (in red on the left of the picture). Can you show me on the schematic what two versions you are referring to? I am only seeing the 990 ( I marked it in red on the right side)
Expert:  William Herren replied 6 months ago.
Here
Customer: replied 6 months ago.
I see what you are saying and that would mean that there is no OCP on my truck. Let's assume for the conversation's sake that you are correct, If it is connected directly to the ground on the starter stud, how is it becoming hot at the relay at the fire wall?
Expert:  William Herren replied 6 months ago.
It has to be shorted how in the wiring somewhere. That is why I recommend removing it and taping it up and making a new ground.
Customer: replied 6 months ago.
I am just having a hard time accepting that a ground wire would short and turn into a hot wire (only when commanded to by the ignition switch) without burning itself up or popping a fuse. Usually it's the other way around where a hot wire shorts out by rubbing against something in the truck.
Expert:  William Herren replied 6 months ago.
I couldn't say, I'm not there to do all the checks. I would check the wiring good, and double check any work that I have recently performed. I hope I have answered and provided you with all the information to get you back going. If so please rate 5 stars. If more information is needed please feel free to ask.
Customer: replied 6 months ago.
I do apologize but the info you have provided me with, unfortunately for me, has not gotten me "back up and going". We are stuck at square one. With all do respect you are asking me to rate you at 5 stars but no solution was provided. you are saying "If more information is needed please feel free to ask". In actuality you have no more true info left to give that would help me fix my truck. I am stuck between a rock and a hard place. I am sure that this has happened before on Volvo truck before. I am sure you are knowledgeable but not in this matter. I just need to find a tech that can say " Yeah we get that a lot on Volvos. It is your such & such & such."
My only other options are talk to another technician or tow it to the dealer.
Expert:  William Herren replied 6 months ago.
I try to resolve all issues. I'm sorry you feel my time has not been of value. I have answered everything you have asked. You have a short on your 990 wire which is making it hot. I am not there to dig through the wire loom to point out exactly where it is. That is something you will have to do. When we first began talking your Volvo wouldn't start by key, now it will.
Customer: replied 6 months ago.
No sir. The truck still won't start by key because the starter is sitting on the table (I sent you a picture of it). The relay was clicking yes when I temporarily rigged it. And if I wanted to RIG it and wanted to start my truck by bypassing all the electronics, I would have done that with no problem. It does not take a rocket scientist to hook a negative wire from the battery or chassis and tape off 990-A. but that is not what i was looking for when I got on this website. I need a permanent appropriate solution not a temporary one.
Customer: replied 6 months ago.
How can I chat with another tech?
Expert:  William Herren replied 6 months ago.
I understand that. The permanent one will be to find the short in the 990 circuit, or replace the wiring harness. How is it possible for me to do that? We are here to guide you on a correct path. I have given you a correct path which is to either find the short or replace the harness. I will see what I can do about getting you to another tech.
Customer: replied 6 months ago.
Thank you.
Expert:  Daniel Wilson replied 6 months ago.
Hi My name is***** will be glad to help. Do you have any fault codes logged?
Customer: replied 6 months ago.
no.
Customer: replied 6 months ago.
Hi Dan. Did you go through and read the past postings?
Expert:  Daniel Wilson replied 6 months ago.
There is a diode inline at the starter relay. Try swapping starter relays and test the diode inline. It would only have continuity one direction. Ill post some diagrams shortly.
Customer: replied 6 months ago.
At the starter relay? you mean the one on the firewall? If that's what you mean,I replaced it with a new relay at the firewall, but no change in the issue. The wire 990-A keeps coming in hot instead of ground. Somewhere in the cab or truck, the wire 990-A plugs into something that is fried or shorted out which is causing it to be hot instead of ground. I have marked it in blue on the schematic. I just can't figure out if it's a ECM or a box of some sort.
Expert:  Daniel Wilson replied 6 months ago.
The Cathode and anode to the right of the relay on the schematic is the diode. I am not sure physically where on the truck but it is inline in the harness. Click this link for more complete diagrams. Also there is an overcrank protection circuit that disables cranking if the starter cranks for too long to prevent overheating of the starter.Schematics
Customer: replied 6 months ago.
Thank you for the link but I actually have a newer version of that link. I just got of the phone with DELCO. They said that the OCP is built-in on the starter not the truck (and it actually resets after the starter cools down), Plus my starter is a remanufactured starter and it does not have the OCP plug on the end of it. What ever it is that is malfunctioning and causing this problem, it malfunctioned over a period of about 2 months and got worse and more frequent until it finally gave out. Would the diode allow power to flow backwards from 284-A to 990-A?
Expert:  Daniel Wilson replied 6 months ago.
It absolutely would and is highly likely what has failed.
Expert:  Daniel Wilson replied 6 months ago.
You should only have continuity one direction on the diode for current flow. As you see in the diagram that diod and the relay are the only two components connecting the two circuits. If the harness is no shorted between the two and the relay is good, it points directly to the diode.
Customer: replied 6 months ago.
I am heading to the dealer to inquire about the diode as a part to replace. Out of curiosity, on the schematic, What is the relation of the blue circle on the schematic and how does it fit or connect to all this?
Expert:  Daniel Wilson replied 6 months ago.
The blue on the bottom right is if there is no over crank protection( shorting jumper). If you look above it in the red circle it would replace that wiring for no OCP. the diode it the arrow with the flat line across the top.Starting CircuitWhen the ignition switch is turned to the START position,power to energize the starter relay coil is supplied on wire number 284. The starter relay coil is grounded through the overcrank protection switch (or a shorting jumper).The over crank protection (OCP) switch is located inside the starter. This switch is optional. Where the OCP switch is not used, a shorting jumper is used to complete the starter relay coil ground circuit.The OCP switch is designed to open and prevent the starter from turning if the starter becomes excessively hot. It should reset when the starter cools sufficiently.When the starter relay energizes, a connection is made from the starter solenoid BATT terminal (wire 285A) to the starter solenoid SW terminal (wire 285).When the solenoid pulls in, a connection is made internally in the solenoid that connects the battery terminal to the motor terminal. Then the starter begins to crank the engine.
Customer: replied 6 months ago.
So we are basically still looking at the diode for the relay as the culprit?
Expert:  Daniel Wilson replied 6 months ago.
Yes. Unfortunately I do not know where it is located on the actual chassis or if it is an integral part of another component or an inline diode in the wiring harness. But it is shown to the right of the relay in the diagram.
Expert:  Daniel Wilson replied 6 months ago.
General FYI.... This is theory of wiring and Not a Volvo publication. some diodes can look like an inline fuse or inline heat shrunk into the wirehttp://verticalpower.com/docs/Contactor_Wiring.pdf
Customer: replied 6 months ago.
I just got back from the Volvo dealer, but with no answer. The 2 options I am faced with are :
1. Rig it to a ground and by-pass 990-A and risk shorting something else out.... or
2. Pay a technician $135.00 an hour to sort through the wiring.
Expert:  Daniel Wilson replied 6 months ago.
I take it they do not know the diode location? I found a link that should help you out. Click below.Starting and ignition circuit
Customer: replied 6 months ago.
That is correct. They were no real help except confirming what I already know. I'll check out the link when I get home.
Expert:  Daniel Wilson replied 6 months ago.
If they dont know I would opt out of paying them 135 an hour to learn on your truck... Haha The link is some troubleshooting help but does not mention the diode. Check near the starter for some inline fusible links as well. Look for something like this ar what looks like a shorting plug at the end of a connector near the starter solenoid. CLICK HERE
Expert:  Daniel Wilson replied 6 months ago.
This link is better. Starting and charging testing.
Customer: replied 6 months ago.
I went through the wiring and nothing. Looks like I am gonna tow it to a local shop. They said they will charge me a flat fee of 300.00 to find the problem whether it takes them an hour or 24 hours. If they don't find it then I don't pay. I have a feeling they know the problem and I have a feeling it's something simple and stupid. Thank you any way.
Customer: replied 6 months ago.
How do you I get a refund?
Expert:  Daniel Wilson replied 6 months ago.
For thier sake I hope they have a cut off where they hand you back the keys and say sorry we cant spend any more free time on this..... Otherwise they wont stay in business very long unless they find it within the 300 labor time range. The site has your deposit. I am a user of the site just as you. Contact them for your refund. I shut down the links from my fire sharing site since I see you want free information. I dont have time to work for free unfortunately. Good luck. I hope they get you squared away.

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