Bulletin No.: PIT6015B
Published date: 06/11/2024

Preliminary Information
PIT6015B Diagnostic Tips When Having Difficulties Programming Or
Adding Key Fob Transmitters
Models
Brand:

Model:

Model
Years:

VIN:
Engine: Transmissions:
from to

Cadillac

Escalade Models

2021 2024

All

All All

All

Chevrolet

Silverado 1500 New (RPO J22,
VIN Digit 5 = A or D)

2022

All

All All

All

All

All All

All

All

All All

All

All

All All

All

All

All All

All

All

All All

All

All

All All

All

All

All All

All

All

All All

All

Chevrolet Silverado 1500
Chevrolet Silverado 2500/3500 HD
Chevrolet Suburban
Chevrolet Tahoe
GMC

Sierra 1500 New (RPO J22, VIN
Digit 5 = H or U)

GMC

Sierra 1500

GMC

Sierra 2500/3500 HD

GMC

Yukon Models

2023 2024
2024
2021 2024
2021 2024
2022
2023 2024
2024
2021 2024

Involved Region or
Country

North America

Condition

In some cases, when performing the IMMO Immobilizer Learn to
program or add key fob transmitters, there has been some
difficulties or even error messages such as, "0004 DEVICE
CONTROL NOT AVAILABLE" Or "Communication Error".

Cause

The cause of these concerns could be one of many different
possibilities.

Correction:
The information below is only for reference and normal SI diagnostics and programming
instructions should always be followed. When having difficulties programming or learning
key fob transmitters to a vehicle, the following tips may help.
1. If programming new key fobs, verify the correct part number fob is being used. Also,
make sure there is not a VIN already learned to the new key fob by using the EL-52545 and
follow the latest version of bulletin 21-NA-061.

2. Do not assume where the programming fob pocket is located, as it can vary from
vehicle to vehicle. Use the owner's manual to verify the proper location of the
programming fob pocket.
NOTE: If there is still a fob transmitter programmed to the vehicle, one quick test to
determine that the IMMO coil is working properly and you have the correct programming
fob pocket location, is to perform the following:
- Remove the battery from the fob that is still programmed to the vehicle.
- Move all fobs away from the vehicle.
- Try to start the vehicle and the results should be a DIC message stating no fob detected.
- Place the learned fob, with the battery removed, into the programming fob pocket and
try to restart or power up the vehicle. If the vehicle powers up, then you have verified
the IMMO coil is working properly, and the correct programming fob pocket is being used.
3. If there was any reprogramming, a module replaced, or any modules with a current DTC
U1962, then make sure the Serial Data Authentication Configuration (SDAC) has
completed.
4. If there are any "Environment Identifier" DTC's set, they should be addressed.
5. During the IMMO Immobilizer Learn, after the ignition automatically powers on, make
sure to set the parking brake. Also, on vehicles with an Electronic Transmission Range
Shifter, press the "Park" button on the shifter.
IMPORTANT: If the vehicle was towed/moved and the Manual Park Release tool DT-52910
was used to place the transmission in neutral, then it must be removed and the
transmission put back into Park.
6. During the IMMO Immobilizer Learn, only place the key fob transmitter in the
programming fob pocket when instructed, and make sure ALL additional transmitters are
AT LEAST 3 m (9.8 ft) away from the vehicle. Do NOT place key fob transmitters on the
roof, hood, etc. keep them away from the vehicle.
7. During the IMMO Immobilizer Learn, always stay with the TLC computer and the vehicle
at all times so you can follow ALL programming instructions, as SPS will instruct multiple
times to perform various functions. If these instructions are missed, the learn could fail.
8. During the IMMO Immobilizer Learn a "Communication Error" message maybe
displayed. This error has been seen when an aftermarket device is connected inline with
the DLC, see the latest version of bulletin 13-08-116-001H. Inspect and remove any
aftermarket devices.
9. In some rare cases, if the computer/lap top being used to do the IMMO Immobilizer
Learn is inside the vehicle it, could cause interference. Make sure the computer/lap top is
outside the vehicle when performing the IMMO Immobilizer Learn.

10. When performing an IMMO immobilizer learn, there are 6 different
"Immobilizer System Component Programming" functions to choose from listed
in SPS/TLC, see example SI Document ID: 4430507. It is important to read and
select the most appropriate function when performing the IMMO immobilizer
learn.
NOTE: On VIP vehicles, if the "Engine Control Module and Body Control
Module IMMO Learn" function is selected, it will invalidate all previously
learned fobs and in most cases those fobs will not be able to be relearned back
to the vehicle. When this happens, the IMMO learn will indicate "0 fobs
learned" and then ask if you would like to program additional fobs and it will be
stuck in this loop. In these cases, the original fobs will need to be replaced
with new fobs.
11. If a vehicle has other complaints, such as passive entry/start inoperative or
no fob/key detected message, then repair those issues first. Even though the
exterior or interior passive antennas are not used for the IMMO immobilizer
learn there has been some cases where an issue with one of these antennas
has caused the IMMO learn to fail. Below is a GDS2 screen shot of the BCM
Keyless Entry Data List from a 2023 Tahoe. In this example, the vehicle did
have a complaint of the IMMO fob learn not completing/failing, but it also had a
complaint of a no fob detected message. When vehicle the GDS2 data it was

found that one of the antennas was showing "Short to Ground". After repairing
this fault, the IMMO fob learn would now complete successfully.

Version History
Version

3

Modified

05/11/2023 - Created on.
03/22/2024 - Update model list and Correction sections
06/11/2024 - Update to the correction section

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