Lighting - TRM, LED Trailer Lighting

Technical Journal

TITLE:
TRM, LED Trailer Lighting

REF NO:
TJ 21297

ISSUING DEPARTMENT:
Technical Service

CAR MARKET:
United States

PARTNER:
3 US 7510 Volvo Cars North America

ISSUE DATE:
YEAR
2012

MONTH
07

DAY
17

FUNC GROUP:
8923

FUNC DESC:
Towing Hitch

"Fixed Right - First Time"

Attachment





Vehicle Type





CSC Customer Symptom Codes

DTC Diagnostic Trouble Codes

Text

TRM = Trailer Module
BCM = Brake Control Module

DESCRIPTION:
A new TRM which supports LED trailer lighting in addition to conventional bulbs was released in May 2012.

Details such as part numbers and installation instructions are found here:
http://accessories.volvocars.com

When testing this new TRM after installation, it is important to note that:

Using a volt meter or test light on one circuit will give a false indication. This is due to the functionality the TRM uses to detect if a trailer is connected or not. To properly test the function, connect multiple light circuits (simulate a trailer being connected).

Due to a mismatch in SW for older cars, some vehicles may set DTC TRM-U014000 or TRM-C140. These DTCs should be treated as ghost codes and do not need to be addressed.

If BCM DTC U210100 (configuration fault) is set after installation, a BCM reload needs to be performed.

The older TRM (earlier than May 2012) was designed for use with conventional bulbs and should not be used with trailers with LED lighting as it may create the following symptoms:

- The LED lamps on the trailer will pulse when the vehicle is being driven.

- The rear park assist sensors are not disabled, and a constant tone is heard.

- The park assist cameras distance indicators are not turned off.

- Rear fog light is not turned off.