neg doorlock output staying on continuos

Hello        (I have a 1999 chev silverado)

I have put in a prostart ct-3471 tw car starter from Canadian Tire. I hooked up the unit, power door locks,and the arm- disarm feature. I like this thing alot ,it works great.

not sure if it was something I have done with the remote or if something else is going on. The door locks stoped working. when I checked the unit it is giving the neg output continuosly on on the lock and unlock pulse wires at same time. I have tried resetting the module with same results. 

The truck has positive outputs to locking unit.  I have used two relays to reverse polarity.The unit worked great for two or three weeks .Now this is happening but the rest of the unit is working ok .starting properly,security arming, just the locks are continuosly giving output .

I have removed the relays for now and just use the regular factory doorlock for now. any help would be great.

looks like the on board circuit is burnt, it could be from an onrush current from the realys, if they were no diode was placed across the coils.

Thanks for the reply. I guess I messed up .never tried putting one of these in before ,a bit of a challenge for myself.(didnt put in diode)

I suppose there is no way to open unit and repair damages? I have taken apart the four wheel drive selector last week and soldered cracks on the board and replaced all the bulbs in board of my gm radio .Thats the extent of MY electronics wondering if any components  could be unsoldered and replaced or is it massive damage when something cooks in these things? Just a thought,dont like giving in too easy.

Thanks again

If I put the new unit in the vehicle. To prevent damage to unit again ,do I just put the diodes in between each pulse line coming from the unit and each relay that they are connected to .I am thinking this should stop the back feed or back rush of current from relays to the unit (as mentioned earlier posts). What kind of diodes should I get are there alot of different syles of them.12v for sure are there alot of different ratings .

Thanks

Both of these are probably dumb questions to but here it goes.

can I just solder the diodes onto the 85 and 86 pigtails that came with relays or does the diode have to be soldered directly onto the relay. 

second wont the power back feed through the coil itself even though the diode is above it on the terminals  .

sorry for this but I dont understand the power.  my unit pulse a neg12volt pulse on one terminal when activated on lock or unlock depending on what function used and the other is 12 all the time on the other.

I have two relays side by side sharing a common 12v one on terminal 85 on one relay and 86 terminal on the other. then lock pulse and unlock pulse on either 86 or 85 terminal  other.   for the positive to the truck I have terminal 30 both for actuators .  terminal87 12volts on both  87a both grounds

I have a hard time to explain .so I founfd this from apost of Jon 720 (doorlock actuator with remote start)0ct28 ,2009. It is exactly the way I have done it, maybe this will help then you will know how I am looking to put in  diode .sorry if I am dumming out on you but... thanks