Walter Clark
Member
I thought it might be helpful to have a place for people to report on successes and fixes related to the common problems one encounters when opting to replace the factory incandescent bulbs with LED bulbs.
The most common problem swapping in LED lamps for any of the external lamps is a bulb fault, indicated by an illuminated bulb icon on the instrument panel. This is caused by the LED replacements drawing a small fraction of the power the detection circuits expect and the circuits reporting a fault. Another problem (with turn signals) can be rapid flashing, caused by the same reduced current consumption. A third issue seen sometimes is a faint glowing of LED lamps when the circuit is supposed to be off. This is most often seen on interior dome lights and is probably the result of the way such circuits are controlled, which leaves a small potential on the lamp circuit, which is enough for the incredibly efficient LED to produce a small amount of light from.
For my contribution I want to describe my replacement of the backup light bulbs in my 2012.
I chose to go with LED's in the backup lamps in order to create brighter light behind me while backing. I have always felt the stock backup illumination was lacking and it only gets worse when I add a trailer and want to see a bit further.
The LED I picked is the "Phinlion 3600 Lumens 1156 LED Backup Bulb Super Bright P21W BA15S 3497 7506 LED Bulbs for Car Truck RV Back Up Reverse Lights, 6000K Xenon White" currently available on Amazon. Note the 3600 Lumens is for both bulbs. They are 1800 each. These replace the OEM 7506 which are rated for 460lm when new. The OEM lamps are rated to consume 21W each and the LED 8.6W.
When installed in the Sprinter they indeed are MUCH brighter and the white is of the "daylight" variety, but they do cause the bulb out report indicator to come on.
Bit of added info. The Sprinter routes a single wire to the rear (white with blue tracer) to the rear to power the backup lights. That wire is in a small bundle of wires that runs along the drivers side roof-line. Being a single wire to both bulbs it is safe to say the Sprinter sensors for "bulb out" need to trip is around half or less of the expected 42W is being consumed.
I did a little testing and found that with these LEDs I needed to add a load resistor of around 6 ohms between the white/blue wire and ground to satisfy the bulb out monitor. 8 ohms was not enough load in my case. The 6 ohm resistor basically turns 32W or so of current fed toward the backup lights into heat. So one would need a 6ohm 50W resistor here. Also it should be mounted in a safe place because it is going to get hot when the backup lights are on. Luckily, this is such a common problem (CAN bus and flasher errors when converting to LED lights) that there are a ton of little kits being offered using chassis mountable heat sinked 50W 6 ohm resistors, and often they include those crappy inline taps and have useful insulated pigtail wires already soldered to the resistors. I used these: https://www.amazon.com/gp/product/B00L4V9ECY/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1
Anyway, the point is a 6 ohm resistor between the backup lamp power wire and chassis ground eliminated the lamp fault on the instrument cluster for the pair of backup LED lamps.
Also, there are LED replacement lamps sold that claim to be CAN Bus error free. From what I can determine they simply add a resistor within the LED lamp to consume the same current as the incandescent bulb they replace. My main beef with this approach is that heat is the enemy of LED technology as is dramatically shortens their life. Each LED bulb already generates significant heat (5-10W in this case) which the housing must shed. Adding another 20W of heat to that problem just makes it much worse (less reliable). I prefer to generate that heat away from the bulb.
The most common problem swapping in LED lamps for any of the external lamps is a bulb fault, indicated by an illuminated bulb icon on the instrument panel. This is caused by the LED replacements drawing a small fraction of the power the detection circuits expect and the circuits reporting a fault. Another problem (with turn signals) can be rapid flashing, caused by the same reduced current consumption. A third issue seen sometimes is a faint glowing of LED lamps when the circuit is supposed to be off. This is most often seen on interior dome lights and is probably the result of the way such circuits are controlled, which leaves a small potential on the lamp circuit, which is enough for the incredibly efficient LED to produce a small amount of light from.
For my contribution I want to describe my replacement of the backup light bulbs in my 2012.
I chose to go with LED's in the backup lamps in order to create brighter light behind me while backing. I have always felt the stock backup illumination was lacking and it only gets worse when I add a trailer and want to see a bit further.
The LED I picked is the "Phinlion 3600 Lumens 1156 LED Backup Bulb Super Bright P21W BA15S 3497 7506 LED Bulbs for Car Truck RV Back Up Reverse Lights, 6000K Xenon White" currently available on Amazon. Note the 3600 Lumens is for both bulbs. They are 1800 each. These replace the OEM 7506 which are rated for 460lm when new. The OEM lamps are rated to consume 21W each and the LED 8.6W.
When installed in the Sprinter they indeed are MUCH brighter and the white is of the "daylight" variety, but they do cause the bulb out report indicator to come on.
Bit of added info. The Sprinter routes a single wire to the rear (white with blue tracer) to the rear to power the backup lights. That wire is in a small bundle of wires that runs along the drivers side roof-line. Being a single wire to both bulbs it is safe to say the Sprinter sensors for "bulb out" need to trip is around half or less of the expected 42W is being consumed.
I did a little testing and found that with these LEDs I needed to add a load resistor of around 6 ohms between the white/blue wire and ground to satisfy the bulb out monitor. 8 ohms was not enough load in my case. The 6 ohm resistor basically turns 32W or so of current fed toward the backup lights into heat. So one would need a 6ohm 50W resistor here. Also it should be mounted in a safe place because it is going to get hot when the backup lights are on. Luckily, this is such a common problem (CAN bus and flasher errors when converting to LED lights) that there are a ton of little kits being offered using chassis mountable heat sinked 50W 6 ohm resistors, and often they include those crappy inline taps and have useful insulated pigtail wires already soldered to the resistors. I used these: https://www.amazon.com/gp/product/B00L4V9ECY/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1
Anyway, the point is a 6 ohm resistor between the backup lamp power wire and chassis ground eliminated the lamp fault on the instrument cluster for the pair of backup LED lamps.
Also, there are LED replacement lamps sold that claim to be CAN Bus error free. From what I can determine they simply add a resistor within the LED lamp to consume the same current as the incandescent bulb they replace. My main beef with this approach is that heat is the enemy of LED technology as is dramatically shortens their life. Each LED bulb already generates significant heat (5-10W in this case) which the housing must shed. Adding another 20W of heat to that problem just makes it much worse (less reliable). I prefer to generate that heat away from the bulb.