You should see just three digit codes.
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
Almost all parts sources are incorrect and show that 94-96 h a Grey module.
The Correct Motorcraft part number for the 94-96 BLACK CCD Ignition Modules is a DY1077 (supersedes DY679, DY667, DY645).
Here is a 212 troubleshooting article for a 95 F 150, but same for your 94 Bronco
DTC 212 indicates a loss of IDM input to the PCM; "...Open harness circuit. Shorted harness circuit. Damaged Ignition Control Module (ICM). Damaged Powertrain Control Module (PCM)..." READ MORE
Source: by Jim
But this set of tests includes use of Ford's old Break-Out Box; so, as I mentioned in another thread here; In place of the break-out box, go to the EEC connector pin instead; Substitute EEC connector pin Number for breakout box number
EEC IV Connector Pin Diagram
Source: by Fireguy50 (Ryan M) at
EEC IV Connector Pin LEGEND Bronco & Ford Truck & Van: 4.9, 460, 5.0, 5.8;
Source: by Ryan M (Fireguy50) at Ford Fuel Injection
Btw, On 21 May, 2019 I purchased a 96 Ford Bronco 5.0 ignition control module,* DY 1077 from Rock Auto.
Here is the RA DY 1077 advertisement showing Motorcraft Logo.
I received it yesterday and noticed the usual Motorcraft logo wasn't impressed on*it.*
Picture shows the only side with information impressed.
The box looked the same as what I have purchased in past from our local Ford dealership.
This is the Wal-Mart DY 1077 with the Motorcraft Logo.
I e mailed Ford Global Brand Protection and asked, "is this is a genuine Mototocraft part?"
The RA ICM is now in the Bronco and there is no CEL. Had to install it because we need the Bronco today to drive to school to pick up grandson, then drive to retrieve #4 son's vehicle, transport another off spring to a doc, etc.
If ICM is not genuine Motorcraft, I'll replace it, then deal with RA.
"What Is Global Brand Protection?
The Global Brand Protection group exists to protect the consumer by ensuring high quality original equipment parts are used in your vehicle that are recommended by Ford Motor Company. Counterfeit products potentially compromise consumer expectations because they do not meet Ford Motor Company’s rigorous testing and quality control standards..."
Ford | Global Brand Protection
Received e mail back from Ford Motor Company Global Brand Protection;
"...After reviewing the information you provided, the part you purchased appears to be genuine
. The OE current model part does not have a Motorcraft/Ford logo on it and looks like the part in your photo. Since the vehicle model year for this part is very old the supplier of the part most likely has changed. Also we have not had any prior issues with Rock Auto selling non-genuine parts."
Ignition Control Module Removal
Remove two screws retaining ignition control module (ICM) (12A297) heat sink assembly to left fender apron.
Disconnect harness connector from ignition control module.
Remove two screws retaining ignition control module to heat sink and remove ignition control module.
Coat ignition control module baseplate with silicone compound, approximately 0.0179mm (1/32-inch) thick. Use Silicone Dielectric Compound (WA-10) D7AZ-19A331-A or equivalent meeting Ford specification ESE-M1C171-A.
Dielectric vs Thermal Grease Ignition Control Module (ICM) discussion @ http://www.fullsizebronco.com/forum/...al-grease.html
Position ignition control module onto heat sink and tighten two retaining screws to 1.2-1.8 Nm (11-16 lb-in).
Install ignition control module heat sink assembly on left fender apron using two retaining screws, and tighten to 9-14 Nm (80-124 lb-in).
Connect wiring to ignition control module.
Timing Adjustment by sackman9975 @ https://www.fullsizebronco.com/forum...302-351-a.html
For posterity; Spark Output (SPOUT) Connector Location (near driver's side hood hinge) in a 94 5.0
Source: by sewiv (Sandy)
Ignition, etc Wiring Diagrams in a 94 EVTM by Mikey350 @ https://www.supermotors.net/registry/23082/77071-2
E4OD Transmission Control Indicator Light (TCIL), it is a LED and overdrive on/off switch at end of the Transmission shifter stalk; flashing OD light is an indication of a transmission related trouble code in the Powertrain Control Module (PCM).
Is it flashing while driving?
When it loses power, what is the RPM reading? (Assuming you have a tach). From a fading memory,
I believe the EEC IV Limits revs at 5,500 rpm.
Some Ford Lack/Loss of Power in Acceleration or Cruise Suspects;
Although you did test vacuum lines, etc., see my leak diagnosis link in post #11 it includes HVAC System
One way to do a quick check is to grab a vacuum gauge. Some parts stores will loan you a gauge with refundable deposit.
The vacuum gauge should read between 15 and 22 in-Hg depending upon the engine condition and the altitude at which the test is performed. SUBTRACT ONE INCH FROM THE SPECIFIED READING FOR EVERY 1,000 FEET OF ELEVATION ABOVE SEA LEVEL.
The reading should be quite steady. .
When engine is rapidly accelerated (dotted needle), needle will drop to a low (not to zero) reading. When throttle is suddenly released, the needle will snap back up to a higher than normal figure.
When vacuum leaks are indicated, search out and correct the condition. Excess air leaking into the system will upset the fuel mixture and cause conditions such as rough idle, missing on acceleration, or burned valves. Or Air Conditioning when in MAX mode may switch to Defrost
Air filter, is it relatively clean?
Air inlet atop radiator support to filter box and to throttle body; look for obstruction; damaged tubing
Transmission Fluid; Observe color and odor of the fluid. It should be red, not brown or black. Odor may indicate overheating condition, clutch disc or band failure. Use an absorbent white facial tissue and wipe the fluid level indicator. Examine the stain for evidence of solid particles and for engine coolant signs (gum or varnish on fluid level indicator).
If particles are present in the fluid or there is evidence of engine coolant or water, the transmission pan must be removed for further inspection.
Fuel quality; Oxidized fuel often turns darker over time and may even smell sour. You can check stored gasoline by pouring some into a clear glass container and comparing it side-by-side with known fresh gasoline. If your old sample looks noticeably darker than the fresh gas, you have strong evidence the gas has gone bad.
Electrical connectors; inspect for corrosion, etc at coil, firewall, ICM, distributor, PCM, etc. especially those with broken locking tabs.
Is Radiator obstructed? (This this is a left-over from Model T days).
Following by WALKER® EXHAUST SYSTEMS:
No Code suspects are:
"Intake manifold vacuum which drops excessively with RPMs. High exhaust back pressure (greater than 1.5 psi at idle and 3 psi at 2000 rpms on most vehicles).
Passageways within the muffler
, resonator or converter have become blocked or restricted. This could be caused by rusted partitions within the muffler breaking away from their original positions and blocking exhaust flow. It can also be caused by chunks of converter substrate material caught in the muffler or from excessive carbon build up in the converter. Another possible source of restriction is crushed exhaust pipes or internal air gap pipe failure. Inspect the exhaust system for crushed, bent or otherwise restricted pipes. Replace or repair as required. If pipes look good, temporarily remove the O2 sensor ahead of the converter. If symptoms are still present inspect for internal air gap pipe restriction ahead of the converter. If symptoms are no longer present, reinstall the front O2 sensor, remove the O2 sensor behind the converter and retest the vehicle. If symptoms are still present the converter is causing the restriction. Check for rich condition, excessive oil consumption, misfires or other root cause of failure. If symptoms are no longer present with the rear O2 sensor removed, the restriction is in the muffler or resonator. Inspect and replace resonator or muffler assembly as required.
Leaks in the exhaust system can affect O2 (Oxygen) storage in the converter and lead to improper O2 (Oxygen) Sensor readings, affecting the AFR (Air / Fuel Ratio) balance. Check all weld areas for cracks, especially O2 sensor ports.
Check all pipe connections for improper alignment or burnt gaskets.
Check all clamp connections for leaks.
Pay close attention to any flex-pipe in the system.
Oxygen Sensor Identification & Location; "...Regardless of how the engine is mounted in the vehicle, conventional or transverse, the HO2S naming convention stays the same in relationship to engine banks 1 and 2.
Bank 1 will always be the bank containing the #1 cylinder (Passenger Side).
Bank 2 is the driver's side. Sensor 1 is upstream sensor, between the engine & the catalytic converter.