Keyless Door Locks

Red Rover, Red Rover, Send Tige Over


Last Changed 2/11/2007
We are used to having remote keyless door locks on our cars so it was inevitable that we wanted *Red Rover* to have keyless door locks also. Of course, with the usual elegance of Volvo circuitry, using a keyless entry kit was problematic. Volvo power door locks are called Central Door Locks. There is a module located under the fuse block that controls the function of the door locks. Basically, using a key or a inside door handle to lock a door caused the other door to also lock. Likewise, unlocking one door will cause the other to unlock. What happens is there is a switch in each door lock assembly that provides a ground path to the Central Lock Module. Application of a ground to the module by turning the key or moving an inside handle forward causes the module to send lock voltage to both door lock motors. The locking process will result in both lock assemblies sending ground to the module. If either lock assembly breaks its ground signal, again from turning the key or moving an inside door handle, the module will send unlock voltage to the lock motors. The lock motors have two wires from the Central Lock Module. On locking, one wire will be ground and the other voltage. On unlocking, the wires reverse roles. This prevents attaching regular keyless lock kits directly to the motors as in typical installation. We found the answer was to control the lock assembly signal from one door using a keyless lock kit.
	We ordered this kit from J.C. Whitney. It came with two transmitters.
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	This is the wire harness description that came in the keyless lock kit. Metering found that there are two single pole double throw relays built into the keyless lock module. The "picked" contacts from each relay are tied together to the "Polarity Input" white lead.
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	This is how we used the keyless lock module with the Central Door Lock Module. We only had to cut one wire to the Central Door Lock Module. The other wires were spliced in.
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Since the Central Door Lock Module is under the fuse block, we stuffed the receiver under the fuse block behind the Central Door Lock Module. We found that since the module was stuff under a lot of electrical stuff, we had to solder a piece of wire to the module antenna to get better range.

Disclaimer: The information in this site is a collection of data we derived from the vendors and from our personal experiences. This information is meant as a learning guide for you to make your own decisions Best practices and code should always be followed. The recommendations we make are from our personal experiences and we do not receive any compensation for those recommendations.

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