Do I need an ABS code reader?

Ok, lets list all brands of ABS/EBS/ECAS for trailers available on Market:

Wabco
Knorr/Bendix/Bosch
Haldex
Eaton

All they support CAN and KWP2000 protocols.

If your trucks is with trailer CAN wiring you will see trailer ABS/EBS as MID137 unit and you can use system manufacter's software with RP1210 adapter.

If there is no trailer can in your truck you can use cut in connetor like this

Sold with Noregon Adapter, found easily this picture with google.

Some trucks indicate trailer ABS/EBS codes on its diagnostic display, like Volvo, MAN, Freightliner, Mercedes and other... You will see MID 137 PID/SID XXX FMI XXX.

Just post code here and I will tell you what's that.

Well, about typical trailer ABS issues. On US trailers 4s/2m ore 2s/2m configurations are used.

Problem #1: broken ABS wheel speed sensor wiring
Problem #2: Bent ABS pole rings when someone changed brake shoes/pads
Problem #3: Air gap between Sensor and tone ring
Problem #4: bad trailer-trucktor wiring
Problem #5: Trailer wire damage
Problem #6: Internal ABS unit damage, usually corroded.

 

'04 Volvo - Version-II, in Diagnostic Menu find Other System and you will see MID 137 XXX XXX code. But it works if your trailer has CAN. Early ABS equipped trailers were with 5 wire cabels, no CAN and there was wire #5 - warning lamp, that's all. From 2000 in Europe and From 2001 in the USA all trailer brake systems are with CAN, and EU made brake controllers (Wabco and Knorr) support KWP2000 (k-line).

Before 2000 there was no diagnostic standard for all trailer systems and munfacters used control unit with LED, blinking fault codes, K-L, CAN of exotic standards (ISO), now they use common comunication standard

If your trailer is with CAN, and trailer-trucktor cabel is OK, you can connect to trailer by truck 9 pin diagnostic connector. You can use adapter connector shown above, but sumtimes there is no diagnostic connector on trailer, no CAN and I have to connect directly to trailer unit from underneath.