The dreaded “crank, no start” scenario can be frustrating for any vehicle owner. One possible culprit behind this issue is the EOBD/OBDII error code P1682. While this code doesn’t directly point to a specific component failure, it often signals a problem within the starting and charging system. This article delves into a personal experience troubleshooting a no-start condition related to this elusive code, highlighting the importance of thorough inspection and a keen eye for detail.
A Cold Case: Tracing the Root of the P1682 Code
The problem began on a sub-freezing morning with a vehicle refusing to start, accompanied by a diagnostic trouble code (DTC) related to the ignition system. Initially suspecting a faulty ignition switch, a replacement was installed. However, the issue persisted on the next frigid morning, leading to further investigation.
The vehicle was moved into a heated garage. After an hour, the engine started without hesitation. This behavior suggested a temperature-sensitive component within the system. Further cold-soak testing confirmed the problem resurfaced when the temperature dropped below 33 degrees Fahrenheit.
Suspecting the Powertrain Control Module (PCM) or Body Control Module (BCM), initial efforts focused on warming these components. However, the problem remained. Attention then shifted to the under-hood fuse and relay box. Applying heat to the fuse box allowed the engine to start, but it would stall when the cover was replaced. Manipulating the fuse box and relays would intermittently restore functionality, sometimes with reduced power.
Removing and warming the relays indoors didn’t solve the problem. Using a hairdryer on the fuse box, however, consistently brought the engine back to life. Through repeated testing, it became clear that the issue resided in the front inboard corner of the fuse box, leading to suspicion of the run/crank relay. However, swapping relays yielded no improvement.
Finally, meticulously checking each fuse revealed a loose connection on the 15-amp fuse for the Throttle Control Module (TCM). The fuse itself was intact, but the forward leg had a poor connection.
The root cause was ultimately traced back to a previously removed fuse tap on the TCM fuse. While removed with good intentions to prevent potential shorts, the remaining prong lost reliable contact in cold temperatures. Adding solder to the fuse leg and reinserting it permanently resolved the starting issue.
Lessons Learned: The Importance of Diligence When Addressing P1682
This experience underscores that the P1682 code, while potentially related to charging system issues, doesn’t always indicate a major component failure. Simple issues, like a loose fuse connection, can manifest as complex problems, especially under specific environmental conditions. Thorough troubleshooting, including a meticulous inspection of all connections within the starting and charging system, is crucial for accurate diagnosis and effective repair. In this case, a seemingly insignificant detail – a loose fuse leg – proved to be the culprit behind a frustrating no-start condition. While the P1682 code provided a starting point, it was persistent investigation and attention to detail that ultimately led to the solution.
