If speed sensor is bad, can yourg check engine light turn on?

Hand brake light as you call it , will come on when other thing's are wrong in the brake system ,not just when the emergency brake is applied . Low fluid in the master cylinder will turn it on, the ABS control module can have it turned on when their is a ABS problem . etc..... With the ABS , check engine light ,emergency brake light on , code's are stored in the EBCM - electronic brake control module . The speedometer info. come's to the instrument cluster from the EBCM . Probably have a bad wheel speed sensor . Your best bet , take it to a qualified repair shop.

pull your old speed-do cable out and lay it on the ground ,turn the end of the cable by hand where it came out of the transmission, when turning look at the other end to see if it is turning, if not bad cable, so go to the bone yard and pick up a used cable.

If you mean the speed sensor for the transmission the check engine light will come on and you won't have a working speedometer.
If you mean the wheel speed sensor the ABS light will be on.

most cases it is the speed sensor and not the speedometer, it usually turns on the check engine light when it fails.

Your vehicle is equipped with 4 of them. They are located at each of the 4 wheels. There are other reasons that the Traction Control light can come on...wheel speeds sensors are not the only reason, athough they are the most common. The traction control system works with the engine/powertrain control system and with the antilock brake system. A bad wheel speed sensor will usually also turn on the Antilock Brake (ABS) light. If the Check Engine light is also on, you could have an engine control problem causing the Trac light to come on.
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If the Trac light is on by itself, you may just have the traction control turned off. The Trac Off switch is located on the steering column.

If none of the above solves your problem, then you will have to scan your computer system to find out why the light is on. ( i.e. failed wheel speed sensor...but which one?)

Start by checking the vehicle speed sensor. It will likely be listed on your vehicle as an output speed sensor and mounted at the transmission. A bad speed sensor will normally log a code in the ECM and turn on the Check Engine light on the instrument panel.

There is a sensor at the top of the rear differential for the ABS system. That sensor went bad and replacing it took care of the problem. What caused mine to go bad was apperantly water got into the differential when launching and loading my boat. check to see if gear lube needs to be replaced also.
The answer above is perfectly correct. When the ABS sensor on the diff goes bad the speedo no longer will work, the odometer stops recording mileage and both brake and ABS light comes on. You also loose O/D or "Lock-up" in the torque converter. The sensor is inexpensive and can be changed in about 30 mins. Good Luck!
I second the second answer :) My ABS light was on, my BRAKE light was on, my CHECK ENGINE light was on, my SPEEDOMETER wouldn't work below 35 mph, then quit working alltogether. Once the speedomenter quit working the odometer and cruise control quit working. I replaced the rear differential mounted speed sensor ($33) and then reset the CHECK ENGINE light by disconnecting the positive battery cable for a couple of minutes. EVERYTHING then worked.
Replace rear differential speed sensor as follows:
a) remove parking brake cable bracket (1/2" socket)
b) remove speed sensor bolt (9/16" deep socket)
c) remove metal speed sensor cover
d) remove speed sensor from rear differential housing (use channel lock pliers, twist gently back and forth while applying upward pressure. Once the speed sensor has a small gap between it and the rear differential housing, insert a flat-blade screwdriver and gently apply upward pressure while gently twisting speed sensor back and forth.
e) disconnect speed sensor from speed sensor cable
f) lubricate new sensor with WD-40, insert into rear differential housing. It will NOT go in all the way by hand, so do NOT force it nor hit it with anything made out of metal.
g) replace metal speed sensor cover
h) Insert speed sensor bolt and tighten LIGHTLY until a small amout of pressure is felt. Tap speed sensor with rubber hammer until it pops into housing. Finish tightening of speed sensor bolt.
i) replace brake cable bracket, replace 1/2" nut and tighten
j) disconnect positive battery cable for 2 minutes, reconnect positive battery cable
h) start vehicle, enjoy,

Plug the computer on to the port located under the dash on the drivers side to get a code reading. It sounds like a 02 sensor about to go bad. If you get a 700 area code, its a transmission sensor code.

Hello there, One of the problems Jeeps do have is Transmissions. It is very typical of the sensors and solonoid packs to go bad, Also Jeeps as well have well know problems with the computer causing transmission issues as well.

I suggest taking it to a shop other than a parts store they are great for basic info but a repair shop can actually look at what each sensor is doing in real time.

You are on the right track and I would most definetly address this asap rather than causing internal transmission problems.

Good luck and I hope this helps.

yes and itys a very common problem yu need to change the speed sensor (VSS) on the trans heres how it comes apart