Loss of IDM input to EEC or SPOUT circuit grounded.
212; Ignition Diagnostic Monitor (IDM) Troubleshooting; "...Identifying the correct module for your vehicle can be accomplished in a number of ways. First, always refer to the correct application in the Engine Management catalog. If that information is not available, check the wiring of the vehicle. If pin # 4 of the module gets a start signal (which should be battery voltage) from the starter circuit, it's a "Push Start" system. On the other hand, if pin #4 of the module is wired directly to pin #4 of the ECM, then it's a CCD system (refer to diagram #5)..." READ MUCH MORE Miesk5 NOTE; use BLACK CCD Ignition Modules in 94-96 Broncos; slow to load, Click Impatent?
Source: by Joe D at carquest.com via web.archive.org http://web.archive.org/web/201009191...ett3q00.CQ.pdf
DTC 211, 212 & 213; ping, rough idle, missing at speed; "...Misfiring, Rough Idle, Surge, & Ping-Knock Symptoms, due to a Magnetized Shutter Wheel, (Bronco & all Fords w/EEC IV & TFI); "...Inside the TFI distributor is a Hall-Effect sensor that provides an RPM and POSITION signal to the Ignition module and ECM for fuel and ignition control. Mounted to the distributor shaft is a "shutter-wheel" that passes through the Hall-Effect sensor. The slots or windows cut in the shutter-wheel are what makes the Hall-Effect sensor switch on/off to create the signal it sends out. The shutter-wheel is supposed to be a piece of "dead" steel but can become magnetized. A magnetized wheel can cause very erratic operation of the Hall-Effect and resulting erratic output signal. The Test: There are a couple of ways to check for this condition. One is to simply pull off the distributor cap and see if something steel will "stick" to the shutter-wheel. Make sure that whatever you are using to check the wheel with isn't magnetized itself. A more accurate method would be to watch the wave-form on the "SPOUT" wire with a Vantage or Lab-Scope. The SPOUT is the wire with the connector in it that you unplug to set ignition timing. Monitor the wave-pattern on the SPOUT with the timing-connector in. If there is anything erratic about the wave-form, unplug the timing connector and re-check the wave-form. If the pattern "cleans up" all of a sudden, chances are good that you have a magnetized shutter-wheel. The Fix: Most shutter-wheels can be removed from the distributor shaft with a couple of screws. Everybody seems to have their own way of de-magnetizing the wheels but good success has been had with bulk audio-tape erasers or by placing the wheel in an engine parts cleaning oven and baking it. That last one sounds weird but it works..."
Source: by snapon.com via archive.org and miesk5 at FSB http://www.fullsizebronco.com/forum/show...=193312&page=9
DTC 212; "...IDM is a feedback signal generated by the ignition system and is monitored at pin #4 of the ECM. Its purpose is to diagnose missed ignition primary pulses at the time the ECM commands the Spout signal to fire the coil. Since it is used solely for diagnostic purposes, if this circuit is not operating properly, it will not affect vehicle driveability; & by Seattle FSB- The Ignition Diagnostic Monitor (IDM) signal is a diagnostic signal for the PCM to to verify a coil firing for each PIP signal. If an erratic or missing IDM signal is received, a Diagnostic Trouble Code (DTC 212) is set. An occasional IDM signal may not affect drivability, but can still throw a trouble code. As SigEpBlue has stated, check for an intermittent ground on the spOUT and/or IDM circuit. Also, ensure that you have the correct Ignition Control Module (ICM) and it is wired correctly to the PCM..." Miesk5 NOTE; use BLACK CCD Ignition Modules in 94-96 Broncos
Source: by SMP via SigEpBlue (Steve) & by Seattle FSB (SeattleFSB) at FSB '94 code 212 mystery IDM Resistor ???
more LINKs in my site @ http://www.broncolinks.com/index.php?index=230
218 IDM circuit is malfunctioning
Verify IDM related codes again please.
Loss of IDM signal
J10 DIAGNOSTIC TROUBLE CODE (DTC) 542
DOES ENGINE START?
DTC 542 indicates that one of the following has occurred:
Inertia Fuel Shutoff (IFS) switch not reset or electrically open (if in secondary circuit).
Open circuit between the fuel pump and FPM circuit connection to the power-to-pump circuit.
Poor fuel pump ground.
Fuel pump electrically open.
Fuel pump secondary circuit short to power.
Fuel pump relay contacts always closed.
Open in FPM circuit between PCM and connection to the power-to-pump circuit.
Left/front HO2S short to power (dual HO2S applications).
Damaged Powertrain Control Module (PCM).