Last week the SRS light came on in my Smart. Scanned it and got code B1 053. High resistance in the right squib circuit. When I got this car the P/O had a high power stereo installed. A real hack job. Lots of stuff under the passenger seat. I pulled all that stuff out and all seemed OK. So my first thought was to check all the connections and wiring in the area. After disconnecting the battery, I pulled the passenger seat. All connectors looked fine as did the actual wires. I took a gamble and ordered a seat belt retractor from a junkyard. $75.00 and free shipping. Just put it in, cleared the code and all seem OK.