BIGGSIE
15+ Year Contributor
- 233
- 0
- Sep 17, 2003
-
Hartwick,
New York
Since my recent forum search for ABS and SRS info, I decided to post an informative thread. Im sure there are many DSMers out there that know a lot more than I do so if anyone has any corrections or additions feel free to post them.
ABS- anti lock brake system In most vehicles this system is made up of an electronic hydraulic pump two, three or most commonly four wheel speed sensors (WSS), a g force sensor, a vehicle speed sensor and an ABS control module (EBCM). The EBCM is constantly monitoring the WSS, the vehicle speed sensor, and the G sensor. When the EBCM sees one wheel speed drop to 0mph it will limit the brake force to that wheel relieving lock up. This is why the brake pedal pushes back during ABS activation. When the EBCM sees one wheel speed sensor at 0mph when the brake is not applied, it sets a code for that specific WSS, this is the most common reason for an ABS light to come on. There are many other reasons why the ABS light will come on like a faulty ABS pump, bad relay, g sensor malfunction, etc. Diagnosing an ABS problem should always start with a visual inspection of all brake components, next you will need to retrieve ABS codes to tell you where the problem is. This is where I have run into a problem, our DSMs dont have a diagnostic flash set-up (# of flashes = code). So we need a scan tool. Yet another problem, my 1995 TSI is suppose to have a 6 or 8 pin blue connecter near the steering column under the dash according to the Snap-on Chrysler book. This is where you plug in to scan tool to retrieve and clear codes. If anyone can help this is where we need it.
SRS- safety restraint system This system is made up of impact sensors, a control module, and the airbags themselves. When the impact sensors detect a collision they send an extremely fast signal to the control module, which relays that signal to the air bags deploying them to hopefully save your life. When the control module detects a problem with the air bags or sensors the SRS light will come on. The same blue connector under the dash that I cannot find lets us retrieve and clear trouble codes for the system. Chrysler calls this system CCD (Chrysler Collision Detection). If anyone has any more info to add we would all benefit greatly. Also if anyone has any questions I will do my best to answer them.
ABS- anti lock brake system In most vehicles this system is made up of an electronic hydraulic pump two, three or most commonly four wheel speed sensors (WSS), a g force sensor, a vehicle speed sensor and an ABS control module (EBCM). The EBCM is constantly monitoring the WSS, the vehicle speed sensor, and the G sensor. When the EBCM sees one wheel speed drop to 0mph it will limit the brake force to that wheel relieving lock up. This is why the brake pedal pushes back during ABS activation. When the EBCM sees one wheel speed sensor at 0mph when the brake is not applied, it sets a code for that specific WSS, this is the most common reason for an ABS light to come on. There are many other reasons why the ABS light will come on like a faulty ABS pump, bad relay, g sensor malfunction, etc. Diagnosing an ABS problem should always start with a visual inspection of all brake components, next you will need to retrieve ABS codes to tell you where the problem is. This is where I have run into a problem, our DSMs dont have a diagnostic flash set-up (# of flashes = code). So we need a scan tool. Yet another problem, my 1995 TSI is suppose to have a 6 or 8 pin blue connecter near the steering column under the dash according to the Snap-on Chrysler book. This is where you plug in to scan tool to retrieve and clear codes. If anyone can help this is where we need it.
SRS- safety restraint system This system is made up of impact sensors, a control module, and the airbags themselves. When the impact sensors detect a collision they send an extremely fast signal to the control module, which relays that signal to the air bags deploying them to hopefully save your life. When the control module detects a problem with the air bags or sensors the SRS light will come on. The same blue connector under the dash that I cannot find lets us retrieve and clear trouble codes for the system. Chrysler calls this system CCD (Chrysler Collision Detection). If anyone has any more info to add we would all benefit greatly. Also if anyone has any questions I will do my best to answer them.
