Nothing is more frustrating than going through an extensive repair and then not have the vehicle operate as it should. Fortunately the SureTrack Community is here to come to the rescue. SureTrack community member DAREAUTO had a 2007 Hummer in the shop for a transmission rebuild and when they were done it wasn’t going into lockup as it should. They posed the question to the community, and with the help of fellow community member MIKE1968 and others, they were able to resolve the issue quickly.
The following Community Fix summarizes the interaction between members of the community that led to the solution.
Vehicle
2007 Hummer H3 3.7L
Title
Transmission not going into lockup every time, install fuses.
Complaint
Transmission not going into lockup every time after rebuild and flash of PCM.
Diagnostic Steps Performed/Parts Replaced
Rebuilt transmission, replaced torque converter, TCC solenoids and wiring harness. Used master kit with seals, gaskets and clutches, bored the valve body per update and updated springs. No codes.
Best Answer from Community Member MIKE1968
Like ericsautomotive stated, look for any PIDs that are associated with TCC lockup. Such as ECT, TPS, TCC, BPP, APP, etc. There may be something outside of the transmission causing this issue.
Cause
Checked the brake switch, then went to fuse box found missing fuses for brake switch, cruise control and SDARS (Satellite Digital Audio Radio System).
Correction
Installed the appropriate fuses and that fixed the problem. Transmission operates properly. Thanks guys for heading in the right direction.
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