Turn Signal on '15 Silverado 3500hD

# 07-08-42-006K: Information on Available BCM Calibrations to Restore Bulb Outage Detection on Vehicles Produced by a Second Stage Manufacturer (Upfitter), Turn Signals Flash Fast after Factory Box Removed - (Nov 12, 2015)

Subject: Information on Available BCM Calibrations to Restore Bulb Outage
Detection on Vehicles Produced by a Second Stage Manufacturer
(Upfitter), Turn Signals Flash Fast after Factory Box Removed

Models: 2007-2016 Chevrolet Silverado
2007-2016 GMC Sierra

Attention: This Bulletin also applies to any of the above models that may be
Export vehicles.

This Bulletin has been revised to add the 2016 Model Year. Please discard Corporate Bulletin Number 07-08-42-006J.

^ The information contained in this bulletin applies only to 2500 and 3500 Series trucks that are to be completed by a second stage manufacturer (upfitter) and may need to have the Body Control Module (BCM) rear turn signal bulb outage detection capability changed.

^ 2014 and earlier 1500 Series trucks only have Option # 1 available.

Production vehicles will be manufactured with one of the following BCM rear turn signal bulb outage detection software options:

Notice:Option # 1 is the only option available for 2014 and earlier 1500 Series trucks and is included with all trucks equipped with a pickup box (RPO E63).

1. A standard production vehicle will have BCM software that checks for two bulbs functioning in each rear turn signal bulb circuit. If one or more bulbs are inoperative, the BCM will "fast flash" the Instrument Panel Cluster (IPC) turn signal indicator as required by Federal Motor Vehicle Safety Standard (FMVSS) 108 and Canada Motor Vehicle Safety Standard (CMVSS) 108.

Notice:Option # 2 is available for 2014 and older 2500 and 3500 Series trucks.

2. Certain 2500 and 3500 models can be ordered with a new option (RPO 9U5) where the BCM checks for one bulb functioning in each rear turn signal bulb circuit. If the bulb goes inoperative, the BCM will "fast flash" the Instrument Panel Cluster (IPC) turn signal indicator as required by Federal Motor Vehicle Safety Standard (FMVSS) 108 and Canada Motor Vehicle Safety Standard (CMVSS) 108.

Notice:Option # 3 is available for 2015 and 2016 trucks (available on trucks with box delete ZW9).

3. Models built with a pickup box delete or chassis cab option (RPO ZW9) will be produced with a BCM program that has no turn signal bulb outage detection capability (LED compatible). The IPC turn signal indicator will flash at the same rate no matter how many turn signal bulbs are inoperative.

Note: For 2015 and 2016 trucks, B3951 & B3950 DTCs for rear tail lamps could set on any truck (ZW9 or E63) if LED lamps are installed (or lamps are inoperative). This code is used as an assembly verification but does not affect the function of a properly operating system with LED lights installed.

In some cases, the upfitter may wish to change the turn signal bulb outage detection capability so that the turn signals work correctly with their upfit or to meet certain requirements. This will require contacting the Techline Customer Support Center (TCSC) to open a case and obtain a Vehicle Configuration Index (VCI) number. Advise the TCSC consultant which turn signal bulb outage detection capability is needed from the following list:

1. Factory standard production TWO bulb outage detection.

Notice:Only available on certain Model Year 2007-2013 2500 AND 3500 Series vehicles.

2. Optional (RPO 9U5) ONE bulb outage detection.

Notice:This option is only available on certain Model Year 2007-2014 2500 AND 3500 Series vehicles.

3. NO bulb outage detection (LED compatible).

Notice:This option is only available on 2015 and 2016 trucks and is included on trucks built with the RPO ZW9 box delete option.

The BCM can then be reprogrammed with the correct software.

Warranty Information

As with any vehicle modifications these changes and expenses (from TCSC, parts, labor or other expenses) should not be considered warrantable repairs and should not be charged under warranty. These modifications are considered customer pay. No labor operation is provided.