Upgrading to LED bulbs in a vehicle like the 2010 VW Bug can offer numerous benefits, from enhanced brightness and longevity to a more modern aesthetic. However, sometimes these upgrades can introduce unexpected issues, particularly with a car’s sensitive electronic systems. One common concern revolves around the OBD2 system and potential error signals triggered by the change in bulb type, especially when dealing with turn signals and brake lights. Let’s delve into a user’s experience with a 2010 VW Bug, LED bulb upgrades, and a perplexing glow plug indicator issue that surfaced afterward.
When switching to LEDs, particularly for turn signals, the reduced electrical load compared to traditional incandescent bulbs can often lead to a condition known as hyper-flashing. This rapid blinking of the turn signals occurs because the car’s system detects a bulb outage due to the lower current draw of the LED. To counteract this, resistors are typically installed in parallel with the LED bulb. These resistors mimic the load of a standard bulb, effectively telling the car’s computer that everything is functioning correctly and preventing the hyper-flash. The most convenient and electrically sound location for these resistors is usually near the bulb socket itself, within the tail light assembly. This placement simplifies installation and keeps the added components hidden and protected.
In the case of our 2010 VW Bug owner, the approach was precisely this: resistors were installed at the rear tail lights to manage the LED turn signal conversion. As expected, this resolved the hyper-flashing for the turn signals. However, the situation became more complex when a flashing glow plug indicator light appeared on the dashboard. Intriguingly, this issue seemed intermittent. To address potential problems with the stop lamp circuit, an additional set of resistors was incorporated, resulting in two resistors behind each tail light assembly – one for the turn signal and one for the stop lamp. Despite these efforts, while the turn signals continued to function flawlessly, the mystery of the flashing glow plug indicator persisted.
The intermittent nature of the glow plug light added another layer of confusion. During several trips, the indicator remained off, only to reappear unexpectedly. This sporadic behavior raises questions about whether the glow plug issue is genuinely related to the LED bulb installation or simply a coincidence, perhaps pointing to an unrelated underlying problem within the vehicle’s system. To gain a clearer understanding, the owner plans to utilize a new OBD2 scanner to delve deeper into the car’s diagnostics. This will hopefully shed light on any stored error codes and provide valuable insights into the cause of the flashing glow plug indicator, and whether it has any connection to the recent LED upgrades on this 2010 VW Bug. The next steps involve careful examination of the diagnostic data to differentiate between correlation and causation in this automotive puzzle.
