Grounding i installed my dvd playe but didn't ground it yet i need to know where to ground it and if i need a relay and a switch. I think i answered my own question.

Need to know some specifics for a specifis answer.
To answer in general, Sounds as if you replaced the correct computer temp sensor (it would have a voltage reference signal) and not the gauge sender. The temp may need to reach 235 degrees or so to kick the fan on. Too me that is way too high. But running at a higher temp normally lowers emissions and I think that is the reason for the high temp to kick on a fan.

With a scanner you can see what the temp sensor is reading and when there is a fan request from the computer. Not everyone keeps a scanner for home use.
Do you have A/C and does the fan ever kick on when the A/C is on?

You can try this,
Go to your factory fan relay and figure which is the ground signal wire (the ECM sends a ground signal to trigger the relay. Early wire such as in my 89 IROC is a green with white stripe). Ground this wire with the key on. Does the fan come on?

If the fan comes on, look at the cylinder heads between the exhaust ports. The right side may have a pipe plug towards the rear. Left side it would be up front.
If there is a pipe plug then there is a provision to add a low temp fan switch. Search SummitRacing.com (or another source) for a low temp fan switch. Hypertech makes some. Install that into the port where the pipe plug is (careful of thread sealant as it can interfere with a good ground it needs). Connect the wire from the low temp switch to the ground wire of the relay. You can use a center tap as all you're doing is adding a ground (thats not like something that will draw current which you don't want to do).
This way you have a low temp switch to send a ground signal to the relay and still have the factory computer circuit.

You can get free wire diagrams from autozone.com in the repair section. This way you can look up your specifuc vehicle and see what wires do what and which would be the ground from the ECM.

If you installed a bypass switch then I just had the same problem. Let me just go over the wiring that we will use. As of right now you should have the (green) emergency brake wire and a small (black) ground wire. There is also a larger (black) ground wire that you attached to the vehicle ground plug. You will need an extra length of wire, I used black because it was for ground. Attach one end of this wire into the connection of larger ground wires. Attach the other end with the end of the smaller ground wire. Then you will attach your switch, one wire to the two ground wires, and the green wire to the other. It sounds a little complicated and I hope I didn't confuse you, but what you are really doing in reality is creating two grounds to one end of the switch and the green wire to the other.

If you have the old firmware then all you need to do is ground the parking brake wire..

if you have the new firmware(just bought the system) a toggle switch is involved:
1 - connect e-brake wire from dvd unit to the switch
2 - connect a ground wire from switch to the unit chassis(any good metal grounding surface will do)
3 - pop in a dvd, toggle the switch back and forth 2 or 3 times depending on what wire you placed where...and voilaa!! your dvd system should work in motion!!

This is a problem with break wire. I too expierienced this. It is NOT a problem with radio. You need to ground the break wire in the harness. It is a protection wire so that it knows the emergency break is on. In other words it is supposed to stop you from watching movies while driving. Grounding the wire disbales the feature thinking the break is on. If you want to use the safety feature properly it should be connected to the emergency break switch that is grounded when pulled up or on.

Go to any auto parts store and purchase a four wire relay and wire it up as follows: The relay will have numbers written on the bottom for each pin. The wire from the parking brake from the H/U to 87. Ground to 85 and 30. Remote from the H/U to 86. This will give you an automatic bypass to the DVD lockout. If you want to just put a switch to do this manually you can also. Go to Radio Shack and buy a momentary push button switch, part number 275-1548. Take the green wire coming out of the unit. Strip the wire, and attach it to one of of the pins on the relay switch. It doesn't matter which one. Buy a standard 16 gauge wire from Radio Shack and connect it to the other pin on the switch, then connect the other end of it to a grounded connection on your vehicle. Now, when you play a DVD, the warning screen will come on. Just press the button on the switch and it will go away, since it tricks the receiver into thinking you have engaged the parking brake. Like someone said before, it is illegal in just about all states to have a dvd or other video playing if the driver can see it and the car is moving. This method is used because the lockout not only keeps you from seeing videos but also locks out some features which many feel have nothing to do with safety and they need it.

This what you do. Connect the video wire to a power suppy and install a switch in the power wire. When you put the DVD in and the warning comes up, turn the switch on then off. This will allow you to watch the DVD without the park brake being applied.

There isn't any code that I know of. Most DVD head units have one extra wire in their wiring harnesses, compared to a standard CD head unit. On mine, it's a peach-colored wire, and is the activation wire for the DVD feature. During the installation, the instructions call for this wire to be tapped into the emergency brake indicator light wire. The reason is this:

The e-brake indicator light is what is called a "ground complete" circuit. That means that the bulb always has power applied, but when you pull the brake, that puts a ground to the wire and completes the circuit, allowing it to illuminate. The head unit sees this ground, and activates the DVD player.

In my Jensen unit, I simply ran this wire to a ground (I used a screw near the fuse box), and I put a switch on the wire, so I could break the ground contact at will. Jensen calls for a procedure to activate DVD playback. In their instructions, they tell you to select DVD from the option menu, and when the "lawyer screen" comes up (the one warning you to park before you watch a movie), you release the e-brake for 3-5 seconds, and then reapply it. To simulate that with the switch I used, I leave the switch closed (activated), and select DVD. Then I flip the switch "off" for 3-5 seconds, and flip it back "on". This tricks the head unit into thinking I put the e-brake off for a few seconds and then put it back on, and the movie will start. Then I can drive away.

Basically, ground the wire that is used for DVD activation, and put a switch inline on it. Then you can break and reapply the ground in whatever manner is required by the manufacturer of your head unit. If there is no off/on sequence with yours, as there is with mine, simply ground the wire to a screw inside the dashboard and you're done.

1. Ground the E-Brake wire.

2. Insert a DVD
Let it play until you hear sound
Press STOP twice on remote
Enter 26604
Press ENTER

U have to ground enywere in the car on the METAL surface with a selftaping screw

If your getting the "Can't view dvd in drivers view must apply parking brake" you need to recheck your ground. You might want to try another location for the ground. If the unit is VM9410 you can simply ground the parking brake wire and you'll be good to go.