Hey everyone!
I recently bought an INPA K+DCAN USB OBD2 cable with a switch, along with a 20-pin round adapter for my 1998 BMW E46 323i (M52TUB25).
Here are the two cables I purchased:
K+DCAN USB OBD2 cable (with switch): https://www.amazon.nl/OTKEFDI-Inpa-Ediabas-Expert-Rheingold/dp/B07K52N1TY/ref=mp_s_a_1_1?crid=QZ04874HUF07&dib=eyJ2IjoiMSJ9.3WzywYqDN3Innjufa_htfH03XH5LhJstOKFzvK03GSbERu8Qy6LFRv2Z3VbMecT3VqVqByBgboPtiLNcfFhE5rN7olk95VSUBkM_oaV0VVY.PmzHvG05zpiObmChZhE6SakWu7mDG8-b3XEsDpjdDRY&dib_tag=se&keywords=otkefdi+inpq&qid=1793116865&sprefix=otkefdi+inpq%2Caps%2C132&sr=8-1
OBD2 to BMW 20-pin adapter: https://www.amazon.nl/gp/aw/d/B07YQQ2M1M?psc=1&ref=ppx_pop_mob_b_asin_title
I installed all the necessary software using Mike’s Easy BMW Tools, including INPA.
However, I’m having a strange issue when connecting everything.
Here’s what happens:
I connect the K+DCAN USB cable to my laptop, and Windows recognizes it.
I connect the cable to the 20-pin adapter under the hood of my BMW.
The red LED on the K+DCAN cable lights up for approximately 5–6 seconds.
During those few seconds, INPA actually seems to recognize the connection! Both the Battery and Ignition indicators turn black (filled circles) instead of remaining empty.
As soon as the red LED on the K+DCAN cable turns off, both black circles in INPA disappear and become empty again, as if the connection was lost.
The K+DCAN cable also starts getting extremely hot, to the point where it’s uncomfortable to hold.
The strange part is that this happens even BEFORE turning the ignition to position 2. The key isn’t even turned to the ignition-on position when this happens.
The switch on my K+DCAN cable is currently set to the left position. I haven’t tried switching it to the right because, from what I understand, the left position should be correct for my older E46.
So basically, INPA briefly shows both Battery and Ignition as detected, but after around 5–6 seconds, the red LED goes out, both indicators disappear, and the cable starts overheating.
My questions:
Could this simply be a defective K+DCAN cable?
Could the 20-pin adapter be wired incorrectly or incompatible with my 1998 E46?
Does the switch position matter for my particular model?
Has anyone experienced a K+DCAN cable overheating and the red LED turning off after a few seconds?
Why would INPA briefly detect both Battery and Ignition, even though the ignition isn’t switched on?
Is there anything I can safely check before ordering another cable?
I’ve disconnected everything for now because I’m worried about damaging my laptop or the car’s electronics.
Any advice would be greatly appreciated. Thanks in advance!