diff --git a/pyren/mod_elm.py b/pyren/mod_elm.py
index 4bbc1f9..e7fc0ee 100644
--- a/pyren/mod_elm.py
+++ b/pyren/mod_elm.py
@@ -604,9 +604,14 @@ class ELM:
             self.lf.flush()
 
         # check OBDLink
-        elm_rsp = self.cmd("STPR")
+        elm_rsp = self.cmd("STI")
         if elm_rsp and '?' not in elm_rsp:
-            mod_globals.opt_obdlink = True
+            firmware_version = elm_rsp.split(" ")[-1]
+            firmware_version = firmware_version.split(".")
+            version_number = int(''.join([re.sub('\D', '', version) for version in firmware_version]))
+            stpx_introduced_in_version_number = 420 #STN1110 got STPX last in version v4.2.0
+            if version_number >= stpx_introduced_in_version_number:
+                mod_globals.opt_obdlink = True
 
             # check STN
             elm_rsp = self.cmd("STP 53")