The check engine warning light is one of the most frustrating lights to see on your dashboard. It gives a bad feeling. You can’t stop thinking about it. You will keep wondering what the problem could be until it is fixed. Sometimes, you can even go to the extent of thinking whether the problem is minor or major.
Anytime the check engine warning light appears on your dashboard, it means that something is wrong with your engine, or something is wrong with the car that probably affects the engine of the car. As we all know, so many things can cause a check engine light to come on, but will low transmission fluid cause a check engine light to come on?
Yes, a low transmission oil may cause the check engine light to come on. When your car’s transmission fluid is extremely low, it can lead to problems within the transmission that can trigger fault codes, causing the check engine light to come on.
Will Low Transmission Fluid Cause Check Engine Light?
Yes, though not in all cases but a low transmission fluid can cause the check engine light to come on your dashboard.
Having a low transmission fluid may not cause the check engine light to come on until the low fluid causes a problem that will trigger a fault code on the car’s computer. It is these fault codes that will cause the check engine light to come on.
For example, I’ve had a transmission problem with my Lexus IS350 that triggered the check engine light to come on. I had a transmission fluid leak and by the time I went to have it fixed, it had leaked half of the oil, but the check engine light had not on.
So, while low transmission fluid may not directly cause the check engine light to come on, it can cause a problem in the transmission that will trigger the check engine light to come on.
Be that as it may, it’s worth noting that if your transmission fluid gets extremely low to the extent that the shifting and driveability are affected, it will obviously cause a check engine light to come on.
You can’t have your engine that is struggling to work because of low transmission fluid and expect the check engine light not to come on. In extreme cases, it will trigger a fault code that will make the warning light come on.
How Can Low Transmission Fluid Cause Check Engine Light
Below is how low transmission fluid can indirectly cause the check engine light to come on due to the effects it has on the transmission and its associated sensors and components:
1. Lack of Lubrication in the Transmission
A car’s transmission needs the transmission fluid to function. These functions include lubrication and cooling of the transmission.
However, when the fluid level is low, it may not adequately lubricate the moving parts of the transmission leading to increased friction and heat.
If the fluid is not replaced or topped up in no time, it can cause damage to transmission components. These damaged components will trigger fault codes that will cause the check engine light to come on.
2. Overheating in the Transmission
As the transmission fluid level drops, the transmission can overheat more easily. Overheating can lead to various issues, including damage to the transmission’s clutch plates, seals, and other components.
Some vehicles are equipped with transmission temperature sensors that can detect overheating, and this can trigger the check engine light to come on on your dashboard.
3. Reduction in Hydraulic Pressure
Automatic transmissions rely on hydraulic pressure to engage and disengage gears. Low transmission fluid levels can result in reduced hydraulic pressure, which can lead to poor gear shifting and slippage.
Therefore, if the transmission control module (TCM) detects these problems, it may trigger a fault code which will cause the check engine warning light to come on on your dashboard.
4. Abnormal Transmission Sensor Readings
Some cars are equipped with numerous sensors that monitor various aspects of the transmission’s operation. These sensors can detect issues such as abnormal gear ratios, slipping, or other transmission-related problems.
If low transmission fluid causes these issues, it can lead to sensor readings that can trigger the check engine light to come on.
5. Triggering of Error Codes
When your car’s onboard diagnostic system detects a problem, it stores the trouble codes in its memory. These codes correspond to specific issues or faults.
In the case of low transmission fluid, the system may generate error codes related to transmission or engine performance problems, which can cause the illumination of the check engine light.
It is this code that will make the light come on on your dashboard. If these codes are not present on your car’s computer, the warning light will not come on.
How Does a Car Act When It’s Low on Transmission Fluid?
If you are low on transmission fluid, your car will act in these manners:
- Your Car will be Slipping in and Out of Gears: The transmission will start slipping in and out of gears. You will start to experience a sudden and unexpected change in engine RPM while driving, even when you’re not manually shifting gears.
- Delayed or Rough Shifting: The transmission may hesitate or shift with a noticeable jolt when you try to change gears, whether it’s an automatic or manual transmission.
- Noises from the Transmission: Low transmission fluid can lead to increased friction and heat within the transmission, which can result in grinding or whining noises while the vehicle is in gear.
- Transmission Overheating: Low fluid levels can cause the transmission to overheat, leading to a burning odor which can damage the transmission if care is not taken.
- Difficulty Engaging Gears: You may have trouble getting the vehicle into gear, especially when moving from a stopped position or shifting between drive and reverse.
- Warning Light Will Appear on Your Dashboard: It can cause the warning light to come on on your dashboard.
- Poor Acceleration and Sluggish Performance: A car with low transmission fluid may exhibit reduced power and acceleration due to inefficient gear engagement and slippage. The engine will not be able to give out the power it has because of the delay in shifting and gear slippage.
Low transmission fluid will cause the check engine light to come on if the fluid is too low it affects the performance of the transmission.
If the transmission is struggling to perform, it can transfer some of the problems to the engine by putting too much stress on the engine, triggering a code that will cause the check engine light to come on.
Also, if any of the transmission components get damaged because of the low fluid, it can trigger a fault code that will cause the check engine light to come on.