Buick Regal car ignition lock cylinder malfunction of the car finder function

Failure phenomenon: a 2006 Buick Regal annual output of 2.5 L sedan, mileage 197 000 km. It reflects the owner to unlock the vehicle remote control, normal lock, locked, normal lighting display and speakers unlocking feedback, but there is no car finder function.

Check Analysis: First take the car after the author validation failure phenomenon, and the ignition key is removed after closing the door, pressing a remote control key lock, the vehicle room lamp immediately extinguished, and the headlight light about the speaker beep. After pressing the unlock key, horn ring headlights lit room lights. Press the key to unlock the luggage compartment and found the lock to normal. However, when searching the car key is pressed, the speaker does not ring, not bright headlamps. I suspect remote controller failed, then use the remote control signal tester for testing, each of the keys found were normal. Check according to ideas from simple to complex, I replaced the remote control after a test program, the fault persists.

The vehicle remote control system consists of the following: remote control transmitter, a remote control receiver, BCM, a trunk lid release and a trunk lid release relay actuator. The remote control system has the following features: the driver’s door lock remote control, remote unlocking all the doors, all remote control door locking, unlocking a trunk lid, a remote control and a remote alarm acknowledgment action searching vehicles.


car remote control system works as follows: when the remote controller is operated, the remote control signal transmitter transmits a UHF band (UHF) radio waves. Pressing any button on the remote control, the remote control signal transmitter to the receiver Remote Keyless Entry (RCDLR) transmitting digitally coded signal. Remote Keyless receiver detects the signal transmitter and signal decoding. For lock, unlock, unlock the tailgate and remote alarm instructions, keyless entry receiver controlling unit BCM issuing information corresponding instructions to manipulate the door lock actuator, the actuator tailgate gated lights, horn and headlights to the vehicle body (figure 1). Further, the vehicle body control unit is further capable of enabling the transmitter programming / diagnostic mode.

FIG. 2

The working principle and circuit diagram of the above (FIG. 2), the author analyzes ruled out the possibility of failure of the remote receiver. Action is for the remote receiver to the remote control signal transmitting BCM. The inspection found, BCM normal output enforcementLine functions but not exclusively, is it BCM internal fault it? Analysis of the BCM According to the symptom and not the fault principle was established. Further analysis of BCM function, according to the principle of the control unit, only the normal input in order to have a normal output, the ignition key cylinder Regal is an important input signal BCM, is not defective ignition key cylinder can not enter normal ignition signal it? Author with a key test to find fault lies, not the original ignition key cylinder lock function, in which the ignition key block can be pulled out.

troubleshooting: After replacing the ignition key cylinder, test troubleshooting.

reviewed: BCM according to the position of the ignition key: blocking stop, the ACC (accessory), 0N (ignition), starting off gear and gear speed of 5 to determine the ignition mode. When the ignition key cylinder in the locked block can not be pulled out, BCM will provide an ignition key cylinder corresponding mode, when searching cars function, BCM that the current block is not a lock, so when we look for the remote control car BCM He did not respond.

Further, the control unit of each car normal input are required: power (long supply, ignition power supply), and the grounding sensor signals, the control unit is fault these conditions, only to satisfy the condition of normal output (execution signal voltage execution, execution Ground), our first thought when servicing electrical fault should be normal ldquo; conditions rdquo ;.

(Zhangze Bo)

Leave a Reply

Your email address will not be published. Required fields are marked *