Bobby's....."How to" information and blog

  Power Liftgate Inoperative – Step-by-Step Diagnosis of a Failed Rear Gate Module Introduction Power liftgates are one of those features you don’t think much about—until they stop working. When they fail, it can be frustrating because the system involves multiple inputs, modules, and wiring paths. In this case, I was dealing with a completely inoperative liftgate that wouldn’t respond to any command. Here’s how I approached the diagnosis, step by step, and how it ultimately led to a failed module. Vehicle Concern The main complaint was simple: Power liftgate would not open No response from: Key fob Dash switch Exterior liftgate button The system was completely dead—no movement, no sound, nothing. Initial Inspection & Symptoms First thing I always do is verify the concern myself. Tried the key fob → no operation Tried the dash switch → no operation Tried the rear button → no operation One important observation: The vehicle did acknowledge the key fob command (lights flashed) Th...

  TPMS Sensor Fault Diagnosis: Why a New Sensor Still Won’t Relearn Introduction Tire Pressure Monitoring System (TPMS) faults can be frustrating—especially when the sensors have already been replaced and the system still won’t cooperate. This is a real-world diagnostic case where a recently installed TPMS setup failed during the relearn process, pointing to a deeper issue that needed to be verified the right way. In this post, I’ll walk through exactly how I approached the problem, what failed, and how to properly diagnose a non-communicating TPMS sensor. Vehicle Concern I was called out to inspect a vehicle that had recently had all TPMS sensors replaced. The shop had already installed and attempted to program them, but the system would not complete the relearn procedure. They needed confirmation on what was going wrong before moving forward. Initial Inspection & Symptoms When I arrived, the system was still showing a TPMS fault. The key issue was: Relearn procedure would not...

  Delayed Engagement and Harsh Clunk Into Drive – Diagnosing a GM 8-Speed Transmission Issue Introduction Every now and then, a vehicle comes in with a complaint that doesn’t throw codes but clearly isn’t right. One of those is a delayed engagement when shifting into Drive, followed by a harsh, almost violent clunk. These types of issues can be tricky because they sit right on the line between electronic control and internal mechanical failure. In this case, I walked through a full diagnostic process to determine whether this was something that could be corrected with relearning procedures—or if it pointed to a deeper internal problem. Vehicle Concern The primary concern was: Delayed engagement when shifting into Drive After a few seconds, a sudden and harsh clunk Reverse engagement felt normal Intermittent harsh engagement when selecting lower gears The behavior was consistent enough to rule out driver feel or normal operation. Initial Inspection & Symptoms Right away, I paid ...

  Rear DVD System Not Working? Step-by-Step Diagnosis of a Failed Overhead Video Module Introduction Rear entertainment systems are a great feature—until they stop working. I recently diagnosed a vehicle where the overhead DVD system completely failed. What started as a simple “DVD won’t play” complaint turned into a deeper diagnostic process involving scan data, system behavior, and circuit verification. In this post, I’ll walk you through exactly how I diagnosed the issue step by step, what to look for, and how to avoid misdiagnosis. Vehicle Concern The concern was straightforward: Rear overhead DVD screen would not power on No display at all—completely blank DVD playback was previously acting erratic (play/pause not responding properly) Eventually, the system stopped working entirely The issue had progressed from intermittent malfunction to total failure. Initial Inspection & Symptoms Before hooking up any tools, I always observe system behavior: Inserted a DVD → no response...

  Ford EcoBoost No Oil Pressure Diagnosis: Engine Noise, Timing Codes, and Hard Failure Explained Introduction Every once in a while, a vehicle comes in with a combination of symptoms that immediately raises concern. Oil pressure warning lights, loud engine noise, and multiple timing-related codes are one of those combinations you never ignore. In this case, what started as a check engine light quickly turned into a much more serious mechanical diagnosis. Let’s walk through this real-world diagnostic process step by step and break down how we confirmed a catastrophic oil pressure failure—and why engine replacement was the smartest move. Vehicle Concern The vehicle came in with the following complaints: Check engine light on Oil pressure warning light illuminated Engine running loud and “clattery” Lack of acceleration / poor performance The vehicle had recently been acquired for resale, so prior history was unknown. That always adds a layer of uncertainty—especially when dealing wit...

Intermittent P0300 Misfire with Multiple Communication Codes – Step-by-Step Diagnosis and What It Really Means Introduction Every now and then, you run into a vehicle that throws multiple codes at you, but doesn’t actually act like anything is wrong. That’s exactly what happened in this case. A check engine light came on with a random misfire code, along with several communication and voltage-related codes. But when I got my hands on it, the engine ran perfectly smooth. So the question becomes: is this a real problem, or just a glitch? Let’s walk through how I approached it and how you can avoid chasing ghosts on similar jobs. Vehicle Concern The vehicle came in with a check engine light. No major drivability complaints were noted, but multiple codes were stored across different modules. At first glance, it looked like a mix of engine and network-related issues — which can sometimes send technicians down the wrong path if you’re not careful. Initial Inspection & Symptoms When I fi...

  Infiniti QX60 CVT Judder Codes with Turning Vibration – Full Diagnostic Breakdown Introduction Every now and then, you run into a vehicle that gives you mixed signals —the symptoms point one way, but the data tells a slightly different story. That’s exactly what happened in this case. We had a vehicle come in with complaints of vibration during sharp turns and a rear-end noise , but what we uncovered during diagnosis added another layer: non-clearable CVT judder codes . Let’s walk through this step-by-step the same way I approached it in the bay. Vehicle Concern The primary concerns were: Vibration or “bumping” sensation during sharp turns Noise that seemed to come from the rear of the vehicle No obvious drivability complaints during normal acceleration At first glance, this sounds like a rear driveline or AWD issue , not a transmission problem. Initial Inspection & Symptoms I started with a road test to duplicate the issue. What I observed: During tight turns, there was a no...