International Truck: What Does Range Inhibit Mean? Fix Guide
In most cases, the range inhibit light only comes on in 2 situations. One is that the transmission is locked out for shifting. The other is when you have low transmission fluid. The key to this is understanding the codes that are turned on.
When it comes to certain Allison transmissions, you can see a yellow warning light. This is called the range inhibit light and it is usually just a warning and codes are not sent. But you may have to add more transmission fluid when you get a chance.
To learn more about this topic, just continue to read our article. It has the information you need to know about so you can take the right steps when you see this warning light. Take a few minutes to see how this information keeps you on the road worry-free.
What Does Range Inhibit Mean?
There are meanings to this warning light. The first is that the transmission ‘thinks’ the RPM is either too low or too high to shift gears safely. It will lock the transmission briefly until it reads that those RPMs are at a safe level to shift.
The second meaning is that the fluid is too low and you will need to add some more but only if the warning lights indicate this. The O L O 7 code will indicate the fluid temperature level is too low. The O L L O 7 with the flashing L indicates low transmission fluid.
A third meaning to the inhibit light would be that there is a problem with the wiring or the transmission sensor. You may have to take your vehicle to the dealer to get the code reset and the problem fixed.
Just check your warranty date to make sure you are passed it before working on it yourself. That is an easy code to get confused and at least one owner has done that already.
Understand the codes first before handling the repair yourself. That should save you time and money.
How To Fix Range Inhibit
This will depend on what is wrong with the transmission that triggered the range inhibit light. In many cases, you can simply pull to the side of the road and turn your engine off. Then turn it back on right away.
This should reset the transmission and your driving will be okay. In the case of low fluid, then all you have to do is add some more to the proper level. That should have the transmission working at normal levels once again.
Then for other not so simple problems, you will have to go to a dealer or mechanic and have them fix the failed part that triggered the warning light. Because there are many sensors placed in the transmission, this part could be anyone and it would take some time to track down the broken part.
These sensors are part of the Transmission Control Module and when it is sent incorrect information, it lights up the range inhibit warning light, and then locks the transmission till the right information is sent to it.
Range Inhibited Light on International Trucks
This can be triggered by different issues other than just low fluid and the wrong RPM level. But the first step is to check your fluid to make sure it is at the right level.
As you check the fluid, look for discoloration and a burnt smell. If there is, you have an internal transmission problem that may take a mechanic to fix it. If there is no smell, etc., then check for metal shavings or other debris in your filter.
If there is, then you will have to disassemble the transmission to find the problem and fix it. If your International Truck has the Allison push button selector, then you can pull the code to see what is specifically wrong.
You would have to have the parking brake on and push the arrow buttons at the same time until the fault code access mode is turned on. If you get more than one fault code, you have to troubleshoot each one separately.
Little by little you will get to the right part and get your truck back on the road again. It just means taking a little time to do it.
Range Inhibit Light on Freightliner
When you see this light, it may or may not be a difficult repair to make. To start, try resetting the transmission. Just pull over to the side of the road and turn the truck off. Then turn it back on again and you do not have to wait a long time to do this.
Another fix would be to pull over to the side of the road, leave your engine running, and put the gear into neutral. Pull the parking brake so that it is engaged. Then slowly put the shifter into drive. This should solve the problem but if not…
Try to get to a qualified Allison mechanic. They may have to diagnose the problem, remove the failed part, and then replace it with a new one. There are a variety of parts that can fail and will need to be replaced. This is something you should not do on your own.
Finally, add some transmission fluid. This is probably one of the first three steps to take before you get to the repair and replacement step. A lot of times it is the most common issue and this is something you can do on your own.
Some Final Words
Technology has changed how cars and trucks are driven. It has improved the transmission and other vital parts that driving has been taken to a whole new level and it is not always good.
Check the simple to fix issues first before going to a mechanic. That way you save time and money and can get back on the road quicker. Not every warning light indicates a major problem. The problem can be simple to fix.
