How to test the under Drive Shift Solenoid?
42: Under-Drive Solenoid Circuit (OBD I equipped only). More specifically, it’ll stay in 2nd gear no matter what speed you’re driving the vehicle. This is called in tech terms: Limp In mode. Testing the Under-Drive Shift Solenoid (Shift Solenoid D) is not hard, and in this tutorial I’ll show you how to do it.
When does the under drive solenoid go bad?
When the Under-Drive Shift Solenoid (also known as Shift Solenoid D), inside the Transmission Solenoid Pack, goes bad, you’re gonna’ see these specific symptoms: The check engine light (CEL) will be lit. P0765: Under-Drive (UD) Solenoid Circuit Malfunction (OBD II equipped only). P0765: Shift Solenoid D Malfunction (OBD II equipped only).
Why is my Shift Solenoid not working properly?
Diagnosis is key when it comes to transmission problems, as various issues can cause similar problems. Trouble with wiring or sensors could be at fault instead. A faulty shift solenoid should be replaced. In some cases, the solenoid is integrated into the valve body and isn’t serviceable.
How does the solenoid work in a car?
As you drive, the car’s computer determines which gear is optimal for your speed. The transmission control module (TCM) — the brains of the transmission — will send power to one of the shift solenoids in order to shift gears. Inside the solenoid, there’s a plunger surrounded by a magnetic coil.
How to test shift solenoids on GM 4.3L?
In this article, I’ll show you how to test the transmission shift solenoids (specifically 1-2 solenoid and 2-3 solenoid) on your GM 4.3L, 5.0L, 5.7L pick up, van, SUV. You’ll be surprised just how easy it is to diagnose these shift solenoids when they have failed.
What happens when one of the shift solenoids fails?
When any one of these two shift solenoids fail, the PCM commands the transmission to operate in LIMP IN MODE and this means that the transmission will run in 2nd gear only (no 1st and no 3rd or 4th).
Is the 4L60-E transmission shift solenoid the same part number?
Let’s move on the next subheading and find out what are the most common symptoms when these two buggers fail. You can buy the 4L60-E transmission shift solenoids online (which will save you some bucks). Both the A and B shift solenoids are the same part number.
What to do if your transmission solenoid is stuck?
If the trouble code tells us that it’s stuck or an electrical problem, it is most likely a wiring or shift solenoid problem. Many shift solenoid-related codes can be solved by doing a transmission fluid replacement or carrying out a transmission flush. A transmission fluid change is often not that expensive and worth doing.