Solving Decoding Problems with Auxito 4KP8 Series LED Turn Signal Bulbs
LIST
- THE TEST PURPOSE OF THE AUXITO 4KP8 SERIES
- SPECIFICATIONS OF LED TURN SIGNAL BULB
- THE LED TURN SIGNAL BULB REPLACEMENT
- LED TURN SIGNAL LIGHT BULB REVIEW FROM DANNY
- FINAL THOUGHTS
Abnormal flashing and error codes occur when upgrading the turn signal light bulbs to LEDs on some sensitive vehicles. This happens due to LED light bulbs raw much less power than stock lamps, for some vehicles, especially European vehicles, are equipped with a CANbus system built-in, which will diagnose the power change and cause the error code, flickering on and off, or malfunctioning, etc. Some customers will try to use a resistor decoder to solve the problem, however, it will complicate the whole installation and may not completely solve the problem.
We offer solutions for the new upgraded LED turn signal bulb to mimic the power draw of the original halogen or HID turn signal bulbs, tricking the computer into thinking the bulbs are the same power rate and preventing the vehicle from throwing out any error messages.
The AUIXTO team invited two customers, Danny and Gary, who had decoding problems when installing LED turn signal bulb before, to review the installation and use of new turn signal bulbs.

*This installation and product review was originally written and licensed by Danny, and we thank Danny and Gary for reviewing our products and sharing with us the use of our new LED turn signals!
THE TEST PURPOSE OF THE AUXITO 4KP8 SERIES
“The purpose of this test is to determine whether the new AUXITO 4KP8 series LEDs can pass the CANBUS error problem encountered in other series AUXITO LEDs. Other AUXITO LED Indicators installed in the 2018 BMW X1 F48 would encounter hyper flashing and trip the CANBUS error warning on the onboard computer, even when cleared by activating the turn signals, the CANBUS warning would reappear after driving for some time. The new 4KP8 Series is a hope of solving that problem.”
SPECIFICATIONS OF LED TURN SIGNAL BULB
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Series: 4KP8
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Model:1156/7506/P21W/BA15S, 7440, 7057/bau15s
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Function: Turn signal light
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Voltage: DC12V-24V, 12V cars only
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Current: Initial:2.38A Stable:2.12 A
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Power: Initial: 32.5W, stable: 28.8W
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LED beads: 8pc 1860
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Color: Amber
THE LED TURN SIGNAL BULB REPLACEMENT
Front indicators Installation Steps
Car model: 2018 BMW X1 F48
Bulb: 4KP8 Series BAU15S/7507/PY21W
Step 1: Open bonnet and locate access way to light housing.

Step 2: Move the windshield washer reservoir funnel out of the way (Starboard Side) by pinching retention clip and pulling funnel upwards.
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Step 3: Reach behind tight space and twist the fins of the indicator socket anti-clockwise to unlock, pull the socket out and change a stock light bulb for the AUXITO LED turn signal bulb.
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Step 4: Re-insert socket with new LED turn signal bulb back into housing and lock by twisting fins clockwise, test bulb by activating indicator.
Step 5: Repeat step 3 and 4 for another side.
Rear indicators Installation Steps
Car model: 2018 BMW X1 F48
Bulb: 4KP8 Series BA15S/1156/7506/P21W
Step 1: Locate rear access panel for indicator

Step 2: Use a plastic pry tool and pry out the retention clip. Unscrew the retention knob counterclockwise and remove it.
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Step 3: Use a plastic flat tool and pop out the panel.
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Step 4: Once the panel is removed, use 10mm socket to remove the two washer nuts.
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Step 5: After removing the 2 washer nuts, use the flat pry tool to wedge in between the rear of the light housing and the main body panel, pull light housing out of housing area.
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Step 6: Unplug the electrical cable from the socket by squeezing the clip and carefully unclip the electrical cable from the two cable management holders.

Step 7: Once the electrical cable is removed and the housing is freed from the main body, squeeze the two top retention clips inwards and the third bottom clip outwards on the socket housing board and carefully remove the board from the light housing.

Step 8: Remove the stock rear turn signal bulb from indicator socket (yellow filter) and replace it with AUXITO BA15S 4KP8 LED turn signal bulb.
Step 9: Re-insert socket board into light housing and re-plug electrical cable as well as carefully re-routing cable through cable management clips
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Step 10: Re-insert the light housing against main body area in accordance to the hooking points and re-screw washer nuts.
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Step 10.5: Test Led turn signals by activating indicators.
Step 11: Replace the panel cover and screw on the retention knob and retention clip.
About The 4KP8 Series LED Turn Signal Bulb Road Test
OEM VS. LED
LED TURN SIGNAL LIGHT BULB REVIEW FROM DANNY
The 4KP8 series LEDs work perfectly. It is very bright, bright to the point you can see the amber light beam shine out the front of the car the LEDs and do not hyper flash or trip the CANBUS warning system, it blinks a steady amber and makes the car visually aesthetic, however one problem still arises when the ignition or car is first started the LED turn signal lights flicker in a very dimly lit matter and stops after a few seconds. It is very dim and not that noticeable during the daytime at all, but at night time or in the dark it is noticeable. (see attached photographs)
FINAL THOUGHTS
Summary by Danny
The new 4KP8 series indicator LEDs, in particular, the BA15S and BAU15S work fantastic with the 2018 BMW X1 F48, with no hyper flashing or CANBUS warning but still has the problem of the bulbs flickering dimly when the car ignition is first started. Overall if the dim flickering problem is fixed, the 4KP8 series LED would be absolutely fantastic to put into any modern luxury or any car that has advanced onboard computers.
Summary by Gary
At first, when I did the LED turn signal bulb upgrade, the LED bulb hyper-flashed and showed on the dashboard that the turn signal bulb broken. The new turn signal bulb replacement no problem plug & play ( the ignition had to be running ) was not on assy power so the computer on board recognized the new turn signal bulb. The dispersion of light is at a 180 deg vs a 60 deg pattern for more visible light in the lens. These bulbs solved problems regular LED presented, on my 2008 Honda Pilot the fused box would have had to be removed to install a led resistor flasher cube relay, a 3 hr fix, These Canbus turn signals (yellow) fix my problem in 10 min.
Have any questions about the LED turn signal light or other products? Please feel free to contact us, and our customer service team would be happy to help with all your questions.
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