Hi,
TSOP is a receiver, so, you can use it only if some device is transmitting the IR signal. Ofcourse, you cant have a receiver without a transmitter.
Also, IR transmitters come with different frequencies. TSOP1738 cannot sense IR waves of 40kHz. The convention of TSOP is this:
TSOP17xx, where, xx represents the frequency in kHz. Hence, TSOP1738 is a 38kHz receiver, while, TSOP1740 is a 40kHz receiver.
Now you can use TSOP1738, "if & only if" the vehicle is transmitting IR waves of 38kHz. But its NOT ADVISABLE TO USE IR because, it gets lots of interference from sun light (as it also contains IR Radiations) & also from humans (yes, they do emit small amounts if IR)
So, just see what your pplication is, & decide accordingly.
Thanks & Regards,
Shodhan