97 Escort Electrical Problem

My daughter's escort has had problems tied to the electric system. The speedo would quit working and the transmission shifting erratically. I'd mess with the wiring harness, clean plug contacts, and all would be well for a while.

Now, I have the problem with the wiring that connects to the negative battery post. This is not the ground cable but a section of the wiring harness that connects to the negative post. It has started to buzz/click over and over under the hood when connected. Sounds like a relay somewhere. I pulled the BTN fuse and it stops the buzzing/clicking cycle. Car won't start or even make a sound when trying to start it. Sure hope it's something I can replace and not spend a fortune on.

I recently put a new battery on it and that's when the problems started again with the speedo, tranny shift problem, radio not working, check engine light on. (wasn't on before this). Just dead in the water with this thing. HELP. LOL

ive got the same kidda promblem except when i turn my car off its trys to fire back up and if i leave the battery on over night it gets drained and the resson why theres no noise when u dissconect the battery and then reconect it u gottal use the master key some sort of immobilesier

My Escort is a 92, but I know the ground connections that run to the battery negative terminal are fairly important for the electronics to function. I would ensure all of those wires are well grounded - even if it means soldering them instead of using the original snap-together connections. There are a couple of other places where ground wires are connected to the frame or the engine - and all of them need to be clean and make good connections.
There are ground wires running to the transmission that are also vital.

Thank you both for the replies.

I'll check all the ground wires and solder those that connect from the wiring harness to the negative post.

D-Bass, I dont understand "master key some sort of immobilesier".

I don't have the battery cables disconnected but the noise stops when I pull the BTN fuse.

I don't have any info for the '97 range but the info which I have for the '95 Escorts regarding the BTN fuse is this:

BTN fuse rating: 60 Amps (1.8L) or 40 Amps (1.9L).
Circuits protected: HAZARD, BELT, DOOR LOCK, STOP, ROOM AND TAIL FUSES, HORN FUSE (1.8L ONLY).

If that info applies to your '97 then you might try replacing the BTN fuse and then remove the STOP, ROOM, TAIL and HORN (1.8L only) fuses one at a time to determine which circuit is causing the relay to chatter.

Good advice there from denisond3 regarding the integrity of the various ground leads and connections - corrosion at a ground connection or at a 12Vdc feed connection could easily cause the chattering relay symptom which you describe.

Oh yes, and if the problem turns out to be on one of the circuits protected by those four fuses which feed off the BTN fuse, then this is the info which I have for them:

STOP (20 Amps): HORN (1.9L only), STOP LAMPS

ROOM (15 Amps): COURTESY LAMPS, ENGINE CONTROLS, POWER DOOR LOCKS, RADIO, SHIFT LOCK, WARNING CHIME

TAIL (15 Amps): EXTERIOR LAMPS, INSTRUMENT ILLUMINATION

HORN (20 Amps): HORN (1.8L only)

Thank you sir. I'll pull those fuses one at a time. I recently changed the brake light switch.

I found a more detailed listing of the circuits fed by the BTN, and the other fuses which feed off the BTN. As before, this is for the '95 Escort:

BTN (60A 1.8L, or 40A, 1.9L): Interior lamps, transaxle, Powertrain Control Module (PCM), exterior lamps, horn, power door lock actuator, radio chassis, passive restraint control module, safety belt warning chime.

STOP (20A): Stoplamp, horn (1.9L only), rear hi-mount lamp.

ROOM (10A 1.9L, or 15A 1.8L): Dome and map lamps, safety belt warning chime, ignition key illumination, luggage compartment lamp, vanity mirror lamp, radio chassis (memory), power door lock relay, shift interlock system, Powertrain Control Module (PCM), radio amplifier (memory).

TAIL: (15A): Parking lamps, cornering lamps, rear lamps, license lamps, compartment lamp, instrument panel illumination.

HORN (30A, 1.8L only): Horn

Thank you sir. I reworked the connections at the negative battery post. That made no difference which I figured would happen.

The clicking is apparently at some type of module located below the air filter housing. I'm guessing this is the PCM? The connector is about 3 inches long with about a dozen wires.

The Haynes manual doesn't have much about it. Schematics are not my forte.

The PCM (Power control module) is located in the passenger compartment under the front of the shift console.

The unit you hear buzzing is the CCRM (Constant control relay module).

It contains the relays for:

1. Low and HIgh speed cooling fan for the radiator.
2. Fuel pump
3. PCM
4. Clutch on the air conditoner compressor

Check the BK/Y wire on it that goes to ground.

Anybody know why one of the relays would be chattering. Selectron? Could you help us out on this?

I don't think I'll be much help on this one, unfortunately - my Escort is a diesel so I'm not familiar with the CCRM. I've looked at the data which I have for the '95 Escort range and I can't even see a mention of a CCRM, nor a diagram. I did find a basic diagram (see below) on the Autozone site but it isn't likely to be much help.

I'd say you have two ways of approaching the fault, and that would be to investigate the module itself, or else work on determining which of the relays is chattering. I'd take the latter course, the reason being that just because there's a relay chattering within the CCRM, it doesn't necessarily mean that the source of the fault is within the module - it could be anywhere at all, so I'd use a process of elimination to try to identify which circuit contains the problematic relay.

Davescort97 has listed the relays contained within the module so I'd go to the Haynes manual and identify the fuse (or fuses) which feed each of those circuits, and then remove the fuse feeding each relay, in turn. I'd probably start with the fuse(s) for the cooling fan (do the easy circuits first), then the air-con compressor clutch, then the fuel pump and lastly the PCM. After (hopefully) identifying which relay is chattering by a process of elimination, I'd then use conventional fault-finding techniques to try to locate the source of the problem.

In the event that that process does point to a fault within the CCRM, then if you happen to know anybody who's familar with electronics then it seems like it would be an easy module to work on - apparently it can be opened by drilling out two rivets and then there's a printed circuit board containing the relays, and at least one power transistor. The checks required would be to check the soldering for dry joints, and check the PCB tracks for cracks, then check for continuity through each of the relay coils, then continuity through the relay switching contacts, then check the discrete components - each relay coil will have a protection diode, and then check any other devices such as the power transistor - any electronics tech will know how to do all of that.

I'll make a few notes on what causes relays to chatter but I'll put them in a separate post, to avoid making this one too lengthy. And here's that very basic diagram of the CCRM:

http://img513.imageshack.us/img513/7650/escortccrm2eb4.gif (http://img214.imageshack.us/img214/1998/escortccrmri3.gif)

And just a few words on relays and what might cause a relay to 'chatter' - i.e. to switch on, only to switch off again a moment later, repeatedly. The purpose of a relay is to enable a small control current (typically only milliamps) to control (i.e. switch) a much larger current - that current might be amps or tens of amps. A relay comprises two sections: the coil, and the switch contacts. A small current passing through the coil creates a magnetic field, and this magnetic field causes the contacts to switch. The contacts might be normally open, switching to closed, or they might be normally closed, switching to open. The contacts might also be changeover, switching from one circuit to another circuit, but they all work on that fundamental principle.

A relay might chatter simply because it's faulty - shorted turns in the coil winding, or physical damage, for example, but more often it will chatter because of reduced operating voltage at the relay coil. One common cause is an over-current fault condition in the switched load - 'switched load' meaning whatever the device happens to be which the relay is feeding. The chattering sequence runs like this: the control current is fed to the relay coil - the coil then energises and creates a magnetic field - the relay switching contacts then close and feed current to the load - however, because the load is faulty and drawing too much current, the supply voltage dips and therefore the voltage at the coil dips, and falls below the holding threshold of the relay - the relay coil therefore de-energises and the current flow to the load ceases. At that point the supply voltage will begin to recover and rise again, thus the coil will re-energise, only to drop out again a moment later and so the cycle continues to repeat - that is a relay 'chattering'.

Another common cause would be a bad connection or a bad conductor in the circuit which feeds the coil - e.g. a corroded connection or a damaged cable. A portion of the available voltage will be dropped across that resistance, leaving a lower-than-normal voltage available to operate the coil. If the drop is great enough then the relay will simply fail to energise, but if the voltage is still above the 'pull-in' threshold of the relay then it will energise and switch current to the load. At that point, the supply voltage (unless it's highly regulated) will dip somewhat, causing the voltage at the coil to dip below its holding threshold, and the relay will de-energise and current will cease to flow to the load. Then, of course, the voltage will recover and rise, and the relay will energise, only to drop out again a moment later, and the cycle will continue to repeat and the relay will chatter.

With the relatively sophisticated circuitry in modern engine control systems, I wouldn't rule out the possibility that relay chattering might result if a signal was missing from one of the control systems. Say, for example, a control system instructed a relay coil to energise but then when the load (whatever it might be) was switched on, an input signal was missing from, say, an input sensor - the load circuit might then send a signal back to the control circuit to tell it to switch off (because a fault condition exists). The control circuit might then try again, only to find that the input signal was still missing, and so switch off again, only to try again a moment later - I can't think of an example but I would be keeping that thought at the back of my mind if I was fault-finding on a modern engine with a chattering relay fault.

So that's a few words on relays, but the first step will be to identify which circuit is malfunctioning and then we can take it from there, and I'll help out if I can. Good luck.

I've been thinking some more about this, and the process of elimination, by removing fuses, may not work. Without knowing what exactly is inside of that CCRM, it's difficult to say. I'm thinking though, that the current to activate the coils on all of those relays may come from a single source - it isn't necessarily the case that, for example, the current for the cooling fans (which flows via the fan relay switched contacts) also supplies current to the fan relay coil, and the current for the fuel pump (which flows via the fuel pump relay switched contacts) also supplies current to the fuel pump relay coil, etc. It might be arranged that way but equally it may not, because the coil, and the switched contacts in a relay are, in the electrical sense, completely isolated from each other, so they don't necessarily need to be derived from the same source. Therefore, removing the fuses which actually supply current to each the loads via the switched contacts, might be an irrelevance. It would still be my first step in locating the faulty circuit, but even if you were to remove all of the fuses for all of the loads controlled by the CCRM, the relay may continue to chatter - even if they were all out-of-circuit at the same time.

If that were to happen then I would be thinking in terms of a single source of current for all of the relay coils, and I'd also be thinking in terms of a fault in the control circuitry for those coils. Do you have a diagram in the Haynes manual which indicates what voltages should be present at the terminals of the CCRM, and under what conditions, e.g. in RUN, or OFF, etc? Does the Haynes manual have a schematic of what's inside the CCRM? If you have anything like that and a means of scanning it, or a good close-up photo of the page, then that would help.

Ok, I pulled the first fuse "room" and the noise stopped. Apparently this drained and killed the new battery because it will not charge at all. In fact, not a hint of spark when connecting the jumper cables directly post to post from another vehicle that's running. So I guess it's new battery time and see what happens.

Could the interior light circuit have shorted fully draining the battery?

If the battery in your car was drained/discharged, thats when you would see a spark (not real big but noticeable) when connecting jumper cables to it whose other ends were connected on another good battery. If you connected jumper cables between two batteries that were still charged up - you wouldnt see sparks; after all they would both be at 12 volts more or less.
A dome light circuit would take a couple of days or longer to drain a battery. My Escort domelight has the little map lights, and its easy to miss them being left on, unless you look at the car when its totally dark outside. One of them takes about 4 or 5 days to drain the battery to where it wont start the car.
If the noise stopped when you pulled the 'room' fuse, it has to be something fed by that fuse.
When I put the battery terminals back onto the posts on a car battery, I take the blade of a small penknife, and scrape lightly around the inside of each terminal, then around the outside of each post before I put the terminals back on. This removes any lead oxide buildup, makes for a better connection.

I've never jumped a fully charged battery before I guess. LOL

I took it down and it checked out just fine.

Now the escort is "dead in the water". Turn it to the ON position and just the "check engine" light comes on. Turning to the start position has the same result. Nothing.

Should I look at the EEC now?

I hope someone who knows about the EEC can help you with advice. It sounds like you are now dealing with another bad fuse - either in the fuse box under the hood, or in the smaller fuse box that is located under the dashboard somewhere.
I would also recheck that all connectors are fully seated, fully pushed together. Some of them a inconvenient to reach, to put it mildly.

Now the escort is "dead in the water". Turn it to the ON position and just the "check engine" light comes on. Turning to the start position has the same result. Nothing.
I'm a little confused. Do you mean that the fault symptom has changed, or do you mean that it's dead in the ON and START positions whilst the Room fuse is out-of-circuit?

If it's the latter, then I assume that would be because the Room fuse feeds current to the PCM.

I am curious if this issue was ever figured out? I have exactly the same problem. At first I thought it was a bad battery since it was teh factory original. No with a new battery, I have a draw on the room fuse. I have checked all the lights, it's not them. I think it is the alarm module but have not had a chance to check it yet. Does it need to be reset after a battery change? If so, anybody know how to do that? 1997 Escort sedan.

i had a problem with my ccrm chattering my fuel pump was staying on and also my coolant fan so i changed it and still have a dead battery every night the car has also been chugging when at idle and stalls every now and then. but changing the ccrm took care of the fuel pump and chattering. i read online that the ccrm fails due to a cold solder joint and all you have to do is pop the rivets and re-do the joints. i would suggest using a lead based solder. i see people trying to sell refurbished ccrm's on the internet for 60 bucks. seems like once that chattering started in the ccrm it was really what the problem was just a ripple effect of the original problem i will post anything new i find with my car and hopefully it will help someone else out

Has anybody figured this problem out? I was driving my escort down the highway when I lost electrical power the gauges went dead. The car continued to run for awhile but did not make it home as the battery died. I removed the alternator tested it & it is fine. I charged the battery & the car starts up fine but dies after battery is drained. Any help would be appreciated.