1997 chevy truck power locks

I am looking to add a remote start and keyless entry to my 1997 Chevy full size truck.  It already has power locks.  Do I need additional relays to power the locks, or can I tap into the vehicles relays?  I am assuming the truck is a positive pulse system.  Is that a correct assumption?

If the truck came equipped with keyless entry than relays are not required and install as 3 wire positive pulse. If the truck did not come equipped with keyless entry than relays will be required and install as 5 wire reverse rest at ground.This information is provided only as a reference.

All circuits should be verified with a digital multi-meter prior to making any connections.

Thank you for the quick response.  I just bought the truck used and didn't receive a keyless fob.  I pulled the door switch off and there are more than three wires.  There was about 7 or 8.  I am assuming itst he 5 wire and additional wires for illumination of the switches.  This leads me to a couple of quick quesitons on  wiring of the relays.

Does it matter which switch I wire these from (driver or pass)?

Is it acceptable to use the 12V that is present at the switch to power the relays?

Is there a preferred method of mounting the relays in the door, or run additional wire to the kick panel?

Any help is appreciated.  Thank you.

dkeys, No that is not what I mean, you do not need to access the wires at the switch. Although, 3 and 5 wires do refer to the number of wires at the switch, for this vehicle you do not need to go there. The wires you will need is in the drivers kick panel. Lock = Light Blue Unlock = White Depending on the system the is being installed, you may or may not need relays to operate the locks. If the system have on-board relays, you will not need any additional relays for either configuration. If the system only has outputs, than you need to determine if they are negative outputs or flip-flop (goes + or - depending on lock or unlock signal from system). If they are flip-flop, you will need two diodes, one to each output, with the bands away from the keyless entry unit, if your vehicle original came with keyless entry FROM THE FACTORY. If they are negative only, you will need relays, see attached links for assistance. Check you installation manual to determine if you have on-board relays or the kind of outputs provided. 3 wire positive relay configuration 5 wire relay configuration The following two documents provides some operations details and interface instructions. 3 wire positive tech sheet 5 wire tech sheetThis information is provided only as a reference.

All circuits should be verified with a digital multi-meter prior to making any connections.

Sorry, some of the confusion may have come from how I phrased the last post, and the rest of it came from my ability to see the forest through the trees. 

I was commenting on the fact that I checked the switch to see which method of locking the truck had, as in some of the posts I have read throught the site, it was mentioned that if this year truck had both power locks and power windows, then it may have the 3 wire positive regardless of whether keyless entry was ordered.  My point of the 5 wire comment was stating I didn't think this was the case.  I will probe the wires to insure this is correct,   but am pretty certain its the 5-wire reverse polarity

Where I had my brain fart was I was assuming that since I need to break the wire between the switch and the actuator, that is all in the door.  Not realizing that there is an interface between doors, ala wires in the driver's kick panel with a twin realy set-up. 

The unit I am using has (-) outputs for the door locks.  If I am seeing this clearly (after verifying 5 wire reverse polarity locks), I will wire the realys such that poles 86/87 are +12V, poles 87a go to the switch side of the kick panel wire, poles 30 go to the acuator side of the kick panel wire, and ples 85 go to the remote starter output.

Do I have a good grasp on this?  Or am I missing something?  Can I use the 12+ that is feeding the door switches, or should I pursue another "hot" wire source?

Thanks again for your help as I (obvioulsy) have never wired one of these units before.

Sorry to add more to the confusion, but I did check a bit more at lunch on the unit.  The unit is an Audiovox APS-55C.  The outputs for the door locks are stated as (neg lock / positive unlock) on one wire, and the opposite on the other. Is this the flip/flop you are referring to?  If so, do I still need a diode if I do not currently have keyless entry?  Does my scenario described above still hold true (if it was correct to begin with), or does this change things?

The wiring scheme you have is correct. I do use the +12V wire going to the switch when interfacing a 5 wire system, but make sure you fuse the wire to the relay and not use it to power anything else. The only time I do not use this wire to power the relays is when the vehicle is equipped with a RAP type electrical system where the power is turned off after a predetermined time. Personally, I like to apply +12V to terminal 86 like you stated above instead of 85, just in case the relay used has a built in diode to suppress voltage spikes.This information is provided only as a reference.

All circuits should be verified with a digital multi-meter prior to making any connections.

dkeys23 wrote: Sorry to add more to the confusion, but I did check a bit more at lunch on the unit.  The unit is an Audiovox APS-55C.  The outputs for the door locks are stated as (neg lock / positive unlock) on one wire, and the opposite on the other. Is this the flip/flop you are referring to?  If so, do I still need a diode if I do not currently have keyless entry?  Does my scenario described above still hold true (if it was correct to begin with), or does this change things?

Yes this is what I mean by flip-flop. If you are using relays, you will not need diodes.This information is provided only as a reference.

All circuits should be verified with a digital multi-meter prior to making any connections.

Some comments if I may. There are no mistakes but 91st states the comment about 85 being the negative side of the relay coil, that's because the ISO convention and therefore ALL car manufacturers "go with the flow". It needles me that some alarm manufacturers and some of the diagrammes on this site flip 85 and 86 around, dangerous as 91ST noted because some relays do come with built in diodes. The diodes are there to prevent damage to the circuits switching the relays at 85. It's a high voltage onrush spike that occurs when the relay coil shuts down. For this reason I would place diodes inline on your lock wires from the alarm, 1N4004, bands towards the alarm. In practise I would always do this when feeding out from flip-flop outputs, it conditions the alarm to flip rather than flop.

Thanks once again for your help and insight.  After drawing the schematic, I understand now with your help.  I am a mechanical guy trying to survive in an electrical world.

What size fuse should be used for the relay +12v?