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Was the AIC attached at the time? Posted by Ari [Email] (#2847) [Profile/Gallery] (more from Ari) on Mon, 13 Mar 2006 13:39:15 In Reply to: 97 CSE, AT: AIC - 12v always or only for moment?, Dag, Mon, 13 Mar 2006 11:31:24 Members do not see ads below this line. - Help Keep This Site Online - Signup |
Was the AIC in the circuit at the time? And which pins?
If the AIC wasn't in the circuit at the time, the readings would be invalid. The AIC is part of a closed-loop system,and the control system uses it to close the loop on idle speed. If it isn't in the circuit, the control box will detect this, and declare it bad. The voltage at that point is anybody's guess.
The AIC is a pulse-width modulated system - the control sends 12 volt pulses at varying widths to control the valve. A multi-meter will usually average these signals.
One side of the AIC is hot when the main relay is pulled in. The other leg is controlled by the Trionic system, and all it does is pull it to ground to create the pulses. If you are looking at the Hot side of the AIC (blue/white wire), it'll be 12 volts, and if the engine didn't start, the main relay would probably drop out, giving you zero volts. On the other side (blue/red), it is a switch to ground; if the AIC isn't plugged in, it'll always show ground.
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