Viper 791xv and TachLearning

Printed From: the12volt.com
Forum Name: Car Security and Convenience
Forum Discription: Car Alarms, Keyless Entries, Remote Starters, Immobilizer Bypasses, Sensors, Door Locks, Window Modules, Heated Mirrors, Heated Seats, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=40530
Printed Date: May 18, 2024 at 4:08 PM

Topic: Viper 791xv and TachLearning

Posted By: DaRacerz
Subject: Viper 791xv and TachLearning
Date Posted: October 08, 2004 at 2:53 PM

Hello,

Have an issue and not sure if its because i tapped into wrong wire, brains, or because i don't have something hooked up. Anyways, first let me explain.

I have two codes stored, i guess, and the led is continuously blinking 2 sets and 3 sets when the car is unlocked. Then I put the key in, start the engine, press and hold the vallet button for like 40-50seconds. The led continues to flash in it 2, 3 like flash sequence. No constant light. What gives?

My hook up. 2004 Hyundai Santa Fe. Tach wire hooked up to ECM at WHITE/ Black wire. With meter, Ac measures ~6v, Frequency varies between 47Hz - 350Hz with RPM's as should. The only glitch here, is I do not have the Relay Pack installed. Is that whats causing it? haven't go to it yet.

mark

Replies:

Posted By: Teken
Date Posted: October 08, 2004 at 4:17 PM

The system based on your information detects a low, or no RPM condition. Or a over rev condition. Verify your tach signal again.

The tach for the 2.4 auto is pin 3 on the 26 pin connector. On the manual it is pin 8 in the 12 pin connector. On the 2.7L model it is pin 17 on the 40 pin connector.

If either one fails, use a injector wire. Use the one that is uncommon to the rest in the bank.

Regards

EVIL Teken . . .

Posted By: DaRacerz
Date Posted: October 08, 2004 at 6:45 PM

Ok, here's what I did after your post.

Happen to be a 2.7l

Checked out Pin, and it is at the 40 Pin connector. Didn't count if it was in position 17, but it was there +/- 1 pin offset. WHITE/ Black.

With voltmeter set to Vac it reads ~6.7Vac and this value really doesn't change much if at all. Then, when measuring the frequency it varries from 47Hz (idle) upto about 350Hz getting near redline.

Will try to change the Tach sense tommorrow to the more sensative mode and see if that helps.

Was woundering, could this also be because the vallet button isn't responding? anyway to check other then checkin if the button itself opens/closes with a meter.

Posted By: Teken
Date Posted: October 08, 2004 at 7:01 PM

You are wanting to see the AC voltage vary with RPM. I cannot speak about why you confirmed the frequency as being pertinent.

Regards

EVIL Teken . . .