There are a couple ways to tell if the bulb is working properly. If there is any light projecting out of the lens, the light bulb is most likely not the problem. However, if there is no light, use the light bulb repair guide to remove the bulb, proceed to shine a flashlight through the bulb corridor into the projector. If the flashlight projects through the lens there is a problem with the bulb, if the flashlight doesn't project through the lens there is an obstruction somewhere in your device. Refer to the Merch Source Projector Entertainment troubleshooting page to help find the problem and navigate to the appropriate replacement guide if needed. Merch Source Projector Entertainment II Troubleshooting
The first thing you should do is turn off the lights and try projecting the image on a white wall. If the image still appears to be dark, there are a couple possible problems. The lens could be dirty, or there could be an obstruction or defect in the light bulb setup. Refer to the Merch Source Projector Entertainment II troubleshooting page for further diagnostics. Merch Source Projector Entertainment II Troubleshooting