Key and starting problems. Do I have a bad VAT?
If you want to keep the VATS system in factory working condition (normally recommended) then a VATS replacement is the answer IF the shops diagnosis is correct, BUT generally speaking ALL GM products built in that decade with the VATS system fail for the same reason sooner or later and it's not usually the VATS itself, but in the key resistor reading portion of the ignition switch.
My 97 Riviera had the same difficulty. Sometimes starts perfect. Other times is totally dead, not like a weak battery, but no fuel pump, no ignition, no starter at all. I noticed the 'security light was on on the dash and if I wait for 3 minutes the security resets itself and the car starts fine.
If these symptoms fit then it is the key reader and not the VATS itself.
There are 4 options if this is so.
1. Aggravation unlimited by putting up with it and waiting for 3 minutes whenever it won't start. (not recommended!!! drives you crazy!)
2. Replace the ignition switch and reader and keys (expensive, but the best all around solution if money is not a problem as it keeps your security system intact, around $250-300)
3. You can buy and install (or have installed) a VATS key reader bypass module. (also a bit expensive, like $150-200 installed)
4.My choice- I took my key to Radio Shack and read the resistance or the resistor. There are 12-15 different combinations. Then I bought 2 resistors that added up to that value + 5%. I soldered those together in line with bull nose connector ends. Then I pulled the lower steering column cover and found the 2 wires leading from the ignition switch reader. Be sure to disconnect your battery and leave the big yellow wire alone, that's the airbag!!! The 2 wires are usually run together inside a long outer sleeve similar to shrink rap and they exit the switch from a different position than the normal on/off/accessory etc. wires. Once located I clipped the wires leaving the switch leads dead and installed the matching bull nose connector ends and then plugged my resistors in line. The car now believes it has the proper resistance key inserted. The rest of the VATS system is not affected. Car starts every time!
This solution requires a little bit of time (took me 1 1/2 hours all in all) and just a little know how, but total cost came to $2.79 :)
Nov 13, 2009 |
1990 Oldsmobile Toronado