Auction timer issue after extension in lot

Question

I am working on auction site in asp.net. When we click on increment bid button of each lot , If time in timer is less than 3 minutes then lot time gets extended for 3 minutes but timers of each lot get mismatched by couple of seconds and my client don't want that.

This is calling of JS function to extend timing for lot: 

 

eval('timer' + auctionLotId).cdtime('timer' + auctionLotId + "', '" + auctioncurrtime + "', '" + auctionendtimer + "', " + auctionLotId);

 

This is JS file for updating timer :

 

function cdtime(container, currentTime, targetdate, AuctionLotID) {

if (!document.getElementById || !document.getElementById(container))

return;

this.container = document.getElementById(container);

this.auctionLotID = AuctionLotID;

var now = new Date();

//this.currentTime = new Date(now.getFullYear(), now.getMonth(), now.getDate(), now.getHours(), now.getMinutes(), now.getSeconds());

//this.currentTime = new Date(now.getUTCFullYear(), now.getUTCMonth(), now.getUTCDate(), now.getUTCHours(), now.getUTCMinutes(), now.getUTCSeconds());

this.currentTime = new Date(currentTime);

this.targetdate = new Date(targetdate);

this.currentTime.setSeconds(this.currentTime.getSeconds() - 1);

//alert('currentTime: ' + this.currentTime);

//this.targetdate = new Date(now.getUTCFullYear(), now.getUTCMonth(), now.getUTCDate(), now.getUTCHours(), now.getUTCMinutes(), now.getUTCSeconds());

this.timesup = false;

this.updateTime();

}

cdtime.prototype.resetTimer = function (newdate) {

var thisobj = this;

this.targetdate = new Date(newdate);

this.extended = 1;

this.timesup = false;

//this.updateTime(); //by yogesh

}

cdtime.prototype.updateTime = function () {

//alert(this.currentTime);

var thisobj = this;

this.currentTime.setSeconds(this.currentTime.getSeconds() + 1);

this.tim = setTimeout(function () { thisobj.updateTime() }, 1000); //update time every second

//timer = setTimeout(updatetimer, 1000);

}