I have a 1994 316i and i can't find the location of the abs controller. My abs light is constantly lit and have had it on the diagnostic but not showing any faults. Can you help?

You take it to a qualified repair shop . Traction control light lit ? ABS light On ? DTC'S - diagnostic trouble code's stored ! GM had bad step motor's inside instrument clusters 2003 to 2006 . You take it to a qualified professional that has a factory or equivalent . You don't guess it's a short . That would only cause more problems .

Have you had the vehicle checked for DTC'S - diagnostic trouble codes ? I would start there first . Battery , charging system all good ? What computer , the ABS has a control module all to it self . The Air con has a relay in the under hood fuse box controlled by the PCM / engine computer . If there is a problem with ABS , The EBCM - electronic brake control module will turn on ABS and the red brake light .
A low voltage condition could cause this problem , but I would expect more of the lights to be lit on the dash . Including the check engine light , battery light . This are not connected , Power or ground wise . Have the vehicle checked for codes , that should be the first place to start any diagnostic's always !

What light is lit ? When light's are lit on the instrument cluster , air bag , check engine , ABS etc... usually means there is a problem with that system , an there are DTC'S - diagnostic trouble codes stored in that systems control module . You need to take it to a qualified repair shop an have diagnostics done to see what the problem is .

If your ABS an brake light are lit , there is a DTC - diagnostic trouble code stored in the EBCM - electronic brake control module . You need to diagnose the problem an replace the bad part or fix the wiring issue an then the lights will go out on there own , if fix correctly. Some auto parts stores have a scan tool that can read ABS codes , an they do it for free .

brake and abs light check brake fluid level. The round float in the master cylinder directly controls the 2 dash lights.
The light is NOT directly controlled by the master cylinder float. The light is controlled by the ABS Module, which location depends on your vehicle. There are a number of different reasons the lights come on. If it comes on but shuts back off within seconds, don't worry about it, that occasionally happens when it gets a bad signal ("nonlatching error"). In rear-wheel-drive (RWD) vehicles, it is common for the differential speed sensor in the rear differential to go bad. You can pick up a Haynes manual to find if you can do at-home diagnostics (Temporarily grounding out the diagnostic lead will cause the ABS light to flash out a pattern indicating the error)


Check the Brake Pressure switch ( also known as SPEED CONTROL DEACTIVATION SWITCH ) which is located below the Brake fluid master cylinder for leakage. The leakage can cause both lights to stay on and also cruise control control not working

PRE-DIAGNOSTIC INSPECTIONBefore diagnosing ABS/TCS, perform a comprehensive visual inspection of system as follows.Check ABS/TCS wiring harness connectors for looseness. Check harness routing; pay particular attention to wheel speed sensor wiring harness routing. Check fuses No. 1D, 5B and 6B in instrument panel fuse block. Check fuses No. 1 and 2 in underhood fuse block. Check brake fluid level in master cylinder reservoir. Check brake fluid level in Pressure Modulator Valve (PMV) assembly reservoir. Ensure parking brake is fully released. Ensure parking brake switch is functioning properly. Always perform ABS/TCS system functional check before using DIAGNOSTIC CODE CHARTSThe EBCM/EBTCM has self-diagnostic capability, which can detect system failures. Fault codes stored by EBCM/EBTCM can be displayed using Tech 1 scan tester. There are no provisions for flash code diagnostics.Begin ABS/TCS diagnosis with PRE-DIAGNOSTIC INSPECTION procedure. If failures are found during pre-diagnostic inspection, perform necessary repairs, and proceed with ABS/TCS FUNCTIONAL CHECK. See Fig. 5 .If no failures are found during pre-diagnostic inspection, go to ABS/TCS FUNCTIONAL CHECK. See Fig. 5 . The ABS/TCS FUNCTIONAL CHECK will either indicate ABS/TCS is functioning properly or direct technician to various diagnostic procedures such as diagnostic charts, symptom diagnosis or BRAKE warning light diagnosis.CHART D - TRACTION OFF WARNING LIGHT ON CONTINUOUSLY & NO DTC SET (BUICK WITH UH8 OR U2A INSTRUMENT CLUSTER)Circuit DescriptionWhen ignition switch is first turned to RUN position, EBTCM goes through a self-test, which lasts 2-4 seconds. During self-test, EBTCM commands TRACTION OFF indicator warning light on. Powertrain Control Module (PCM) can also command EBTCM to set a Code 75 which will illuminate TRACTION OFF indicator.Traction control switch is located either on instrument panel center trim plate or driver's front door trim panel. Switch allows driver to select traction control mode (on/off). When traction control system is turned off, TRACTION OFF warning light comes on.EBTCM monitors transaxle temperature through

this dealer is a joke abs maybe faulty sensor traction control try check the fuse on the fuse box if is blow replace if nothing happens needs a computer diagnostic

hia nick....sounds crazy but change or check for a mass air meter fault...99% thats what it will be....good luck matt

Hi, the lights get lit when the brake fluid level in the reservoir falls too low or the fluid level signal is broken due to dirt in the connector. You could remove and install the sensor electric connector, located above the reservoir, and carefully knock the reservoir to release the possibly stuck level sensor.

same problem here, found 3 places that say it is the abs sensor:

Had this problem with my 1999 Ram 1500. 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!

The fix for your truck is the ABS speed sensor located in the top of the differential housing , held in with one stud . Your speedometer is calculated through the ABS controller. Replacing that sensor will fix your problem.