RE: CHECK ENG. CODES - P1670,P1671
P1670/71 equate to Volvo code ECM720A whichis a breakdown in the communication to the immobilizer. It could be a faulty engine control module or a faulty immobilizer control moduleat worst or something simple such as a faulty key or bad wiring connection.
Work was good - retirement is better.
1996 850GLT 2.5 20v Estate Manual.
1995 Peugeot Boxer 2.5Tdi Autosleeper.
1984 244DL, Manual.
1987 744GLE, Manual.
1991 960 3.0 24v, Auto.
1994 940T Wentworth, Auto.