If the shade won't stay down, the pawl-and-ratchet mechanism may need cleaning. Take the shade down and remove the cap at the flat-pin end of the roller. Vacuum out any obvious dust, and clean the mechanism with a soft cloth. Spray silicone lubricant into the mechanism.
Take the roll up blinds down to gain access to the ratchet mechanism. Using a toothpick and some compressed air, remove any debris or dust around the ratchet. Then lubricate the ratchet with some WD-40. Your blinds should now work.
Put a piece of masking tape on the side opposite from the telescoping (uneven) end. Then, re-roll the shade. The extra height that the tape gives will correct the problem.
Remove the blinds from the window and place them on a flat surface. Look for the pin that controls the tension and carefully twist it clockwise to increase tension. This might require pliers if the pin is recessed or difficult to grip.
If you hit resistance, bring the fabric towards you slightly and give it a gentle tug. This should release any tighter springs and allow you to adjust the fabric once again. You can also gently move the fabric from side to side, rocking it until the springs begin to work again.
If you have a shade that is difficult to pull or won't pull down at all, the most likely cause is a tangled cord. Examine the shade and the cord to see where the tangled cord is and unravel it slowly to avoid further entanglement. If the cord is frayed, you may need to replace it with a new one.
Holding the cord at a 45-degree angle, release it to the desired length. Keep tension on the cord until the blinds reach your desired height. Lock the blinds. Move the cord in the opposite direction until the lock catches and the blind can remain at your chosen height.
Most likely the chain mechanism, responsible for raising the fabric, or the roller (the material is wound onto it) is damaged. There may also be damage to the fastening system, guide or cassette.
The clutch system involves a chain or cord that's connected to a clutch mechanism. Pulling the chain or cord allows you to easily adjust the fabric's height to your preferred position. This system allows you to have precise control over the position of your shades. Motorized roller shades are gaining popularity.
If the sprung pin is full compressed and the bracket is touching the barrel of the blind, it will act as a brake. This will make the mechanism stiff to operate and this often indicates that the brackets have been fitted too close. The easiest fix is to try to bend the bracket away from the barrel slightly.
After lowering your blinds to the desired level, it's time to lock them in place. To do this, gently pull the string at a 45-degree angle to the right. You should feel and hear a click when the clutch locks into place. Don't tug, but make sure to give the string a firm tug, so your blinds stay in place.
Loosen Adjusting Mechanism: Carefully loosen the component that applies pressure to the spring (e.g., a screw or bolt) to allow for adjustment. Increase Tension: Proceed to tighten the bolt or apply pressure to incrementally increase the spring's tension. Avoid over-tightening as this can overstress the spring.
Most problems with operating cordless blinds can be resolved by reactivating the cordless tension device. To do this extend the blind until it is fully lowered then raise the blind by pushing up on the middle of the bottom rail. It may take several attempts to reactivate the tension.
For roller shades and blinds, there is usually a problem with the tension spring. You can attempt to fix roller blinds with the following: Take the shade down and manually unroll it to the halfway point, then turn the pin on the spring side of the blind until tension returns.
Pulling down on the roller increases the tension on the spring so the shade stays in place. Occasionally, the spring may uncoil and lose tension, so it doesn't work right. You can just roll with it, though, by simply adjusting the spring.
If the shade won't stay up, the spring is too loose. Pull the shade down enough to turn the roller a few times; if it's extremely loose, pull it down about halfway. Lift the flat-pin end of the roller out of its bracket. Then roll the shade up by hand, keeping it tightly rolled.
Take a reasonably firm but not heavy-handed hold of the bottom of the fabric to keep it taut, and then gently pull the blind down by the chain to try and loosen the jam and free the blind up.