I have a 1991 Dakota that the brake and antilock light come on after less than 10 seconds of going out on startup. If i short out the connector on the passenger side I get a 9 code. I have replaced th

If both the RED brake light and the ABS light are coming on while you are driving the car, you either have an hydraulic failure or there is a problem with your ABS module that can potentially affect your regular service brakes.

The first thing to do would be to check the fluid level in your brake master cylinder. If it is low, you need to find out WHY. There is always a reason for the fluid level to be low. It is NOT SAFE to just add fluid without correcting the problem that caused the fluid level to be low.

If the fluid level is OK, then you must scan your antilock brake module for fault codes. The antilock brake module controls the antilock light and can affect the RED brake light as well. There are many different possible failures that can cause this. There is NO OTHER WAY to know why the antilock module has turned the light on. You can spin your wheels for days, replace a BUNCH of parts and never find the problem if you do not scan the module first.

rear antilock braking system=R.A.B.S.and cheers from U.S.A

Assuming the switch is not the problem, check the bundle of wires that come through the firewall next to the brake fluid reserve. I suspect you have a dead short that needs to be fixed

The antilock brake pump motor is shorted.

go to diferential,on center top its posible you find and speed sensor ok if its there,replace it,if it has antilock light on,it has a and antilock sensor problem ok,go to rear axle.

This truck probably has Rear Wheel Anti-Lock (RWAL) brakes. There is a small black module near master cylinder that is the brain for this system. There are ways to check for diagnostic trouble codes in this system. Once you have any codes set, diagnosis can be fairly simple. PROCEDURE:
Diagnostic Trouble Codes (DTC) 's can be displayed by jumping terminals "A" and "H" of the Data Link Connector and observing the flashing of the "BRAKE" warning light. This should only be done when the brake lamp is "ON".
The terminals must be jumped for about 20 seconds before the code will begin to flash. Count the number of short flashes starting from the long flash. Include the long flash as a count. Sometimes the first count sequence will be short. However, subsequent flashes will be accurate. If there is more than one failure, only the first recognized code will be retained and flashed.

NOTES:
DTC's 6, 9 and 10 will only turn the "BRAKE" lamp on while the fault exists. These are soft codes faults and can only be read with the Tech 1 scan tool.
Do not jump terminals "A" to "H" if the "BRAKE" lamp is not on. Jumping the terminals with the "BRAKE" lamp off will set a false DTC 9. This will turn the "BRAKE" lamp on and disable the antilock system.

1, 11, & 12 ECU Malfunction

2 Open Isolation Valve or Malfunctioning ECU

3 Open Dump Valve or ECU Malfunction

4 Grounded Antilock Valve Reset Switch

5 Eccessive Actuations of the Dump Valve

6 Erratic Speed Signal

7 Shorted Isolation Valve or Faulty ECU

8 Shorted Dump Valve or Faulty ECU

9 Open Circuit to Speed Signal

10 Brake Lamp Switch Circuit

13, 14 and 15 ECU Malfunction

if abs activates when it should not,,, it means abs module senses one or more wheel sensores under 3 mph and the other sensores are above 3 mph. .the cause of this is usualy a bad wheel speed sensor or excessive air gap between the sensor and ringwheel. you need an abs data scanner to hook up and go for a test drive to find out which sensor is the culprit.

thermostat my be stuck closed. check radiator for gunk and junk, check oil if it looks milky then its your head gasket. to reset the check engine light disconnect the neg battery terminal for 30 seconds

fuse #7 is the brake lamp fuse. It also operates the rear antilock brakes and the buzzers.